Tag Archives: Tags

Artefacts in the classroom with Museum in a Box

Post Syndicated from Alex Bate original https://www.raspberrypi.org/blog/museum-in-a-box/

Museum in a Box bridges the gap between museums and schools by creating a more hands-on approach to conservation education through 3D printing and digital making.

Artefacts in the classroom with Museum in a Box || Raspberry Pi Stories

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Fantastic collections and where to find them

Large, impressive statues are truly a sight to be seen. Take for example the 2.4m Hoa Hakananai’a at the British Museum. Its tall stature looms over you as you read its plaque to learn of the statue’s journey from Easter Island to the UK under the care of Captain Cook in 1774, and you can’t help but wonder at how it made it here in one piece.

Hoa Hakananai’a Captain Cook British Museum
Hoa Hakananai’a Captain Cook British Museum

But unless you live near a big city where museums are plentiful, you’re unlikely to see the likes of Hoa Hakananai’a in person. Instead, you have to content yourself with online photos or videos of world-famous artefacts.

And that only accounts for the objects that are on display: conservators estimate that only approximately 5 to 10% of museums’ overall collections are actually on show across the globe. The rest is boxed up in storage, inaccessible to the public due to risk of damage, or simply due to lack of space.

Museum in a Box

Museum in a Box aims to “put museum collections and expert knowledge into your hand, wherever you are in the world,” through modern maker practices such as 3D printing and digital making. With the help of the ‘Scan the World’ movement, an “ambitious initiative whose mission is to archive objects of cultural significance using 3D scanning technologies”, the Museum in a Box team has been able to print small, handheld replicas of some of the world’s most recognisable statues and sculptures.

Museum in a Box Raspberry Pi

Each 3D print gets NFC tags so it can initiate audio playback from a Raspberry Pi that sits snugly within the laser-cut housing of a ‘brain box’. Thus the print can talk directly to us through the magic of wireless technology, replacing the dense, dry text of a museum plaque with engaging speech.

Museum in a Box Raspberry Pi

The Museum in a Box team headed by CEO George Oates (featured in the video above) makes use of these 3D-printed figures alongside original artefacts, postcards, and more to bridge the gap between large, crowded, distant museums and local schools. Modeled after the museum handling collections that used to be sent to schools, Museum in a Box is a cheaper, more accessible alternative. Moreover, it not only allows for hands-on learning, but also encourages children to get directly involved by hacking its technology! With NFC technology readily available to the public, students can curate their own collections about their local area, record their own messages, and send their own box-sized museums on to schools in other towns or countries. In this way, Museum in a Box enables students to explore, and expand the reach of, their own histories.

Moving forward

With the technology perfected and interest in the project ever-growing, Museum in a Box has a busy year ahead. Supporting the new ‘Unstacked’ learning initiative, the team will soon be delivering ten boxes to the Smithsonian Libraries. The team has curated two collections specifically for this: an exploration into Asia-Pacific America experiences of migration to the USA throughout the 20th century, and a look into the history of science.

Smithsonian Library Museum in a Box Raspberry Pi

The team will also be making a box for the British Museum to support their Iraq Scheme initiative, and another box will be heading to the V&A to support their See Red programme. While primarily installed in the Lansbury Micro Museum, the box will also take to the road to visit the local Spotlight high school.

Museum in a Box at Raspberry Fields

Lastly, by far the most exciting thing the Museum in a Box team will be doing this year — in our opinion at least — is showcasing at Raspberry Fields! This is our brand-new festival of digital making that’s taking place on 30 June and 1 July 2018 here in Cambridge, UK. Find more information about it and get your ticket here.

The post Artefacts in the classroom with Museum in a Box appeared first on Raspberry Pi.

Engineering deep dive: Encoding of SCTs in certificates

Post Syndicated from Let's Encrypt - Free SSL/TLS Certificates original https://letsencrypt.org/2018/04/04/sct-encoding.html

<p>Let&rsquo;s Encrypt recently <a href="https://community.letsencrypt.org/t/signed-certificate-timestamps-embedded-in-certificates/57187">launched SCT embedding in
This feature allows browsers to check that a certificate was submitted to a
<a href="https://en.wikipedia.org/wiki/Certificate_Transparency">Certificate Transparency</a>
log. As part of the launch, we did a thorough review
that the encoding of Signed Certificate Timestamps (SCTs) in our certificates
matches the relevant specifications. In this post, I&rsquo;ll dive into the details.
You&rsquo;ll learn more about X.509, ASN.1, DER, and TLS encoding, with references to
the relevant RFCs.</p>

<p>Certificate Transparency offers three ways to deliver SCTs to a browser: In a
TLS extension, in stapled OCSP, or embedded in a certificate. We chose to
implement the embedding method because it would just work for Let&rsquo;s Encrypt
subscribers without additional work. In the SCT embedding method, we submit
a &ldquo;precertificate&rdquo; with a <a href="#poison">poison extension</a> to a set of
CT logs, and get back SCTs. We then issue a real certificate based on the
precertificate, with two changes: The poison extension is removed, and the SCTs
obtained earlier are added in another extension.</p>

<p>Given a certificate, let&rsquo;s first look for the SCT list extension. According to CT (<a href="https://tools.ietf.org/html/rfc6962#section-3.3">RFC 6962
section 3.3</a>),
the extension OID for a list of SCTs is <code></code>. An <a href="http://www.hl7.org/Oid/information.cfm">OID (object
ID)</a> is a series of integers, hierarchically
assigned and globally unique. They are used extensively in X.509, for instance
to uniquely identify extensions.</p>

<p>We can <a href="https://acme-v01.api.letsencrypt.org/acme/cert/031f2484307c9bc511b3123cb236a480d451">download an example certificate</a>,
and view it using OpenSSL (if your OpenSSL is old, it may not display the
detailed information):</p>

<pre><code>$ openssl x509 -noout -text -inform der -in Downloads/031f2484307c9bc511b3123cb236a480d451

CT Precertificate SCTs:
Signed Certificate Timestamp:
Version : v1(0)
Log ID : DB:74:AF:EE:CB:29:EC:B1:FE:CA:3E:71:6D:2C:E5:B9:
Timestamp : Mar 29 18:45:07.993 2018 GMT
Extensions: none
Signature : ecdsa-with-SHA256
Signed Certificate Timestamp:
Version : v1(0)
Log ID : 29:3C:51:96:54:C8:39:65:BA:AA:50:FC:58:07:D4:B7:
Timestamp : Mar 29 18:45:08.010 2018 GMT
Extensions: none
Signature : ecdsa-with-SHA256

<p>Now let&rsquo;s go a little deeper. How is that extension represented in
the certificate? Certificates are expressed in
<a href="https://en.wikipedia.org/wiki/Abstract_Syntax_Notation_One">ASN.1</a>,
which generally refers to both a language for expressing data structures
and a set of formats for encoding them. The most common format,
<a href="https://en.wikipedia.org/wiki/X.690#DER_encoding">DER</a>,
is a tag-length-value format. That is, to encode an object, first you write
down a tag representing its type (usually one byte), then you write
down a number expressing how long the object is, then you write down
the object contents. This is recursive: An object can contain multiple
objects within it, each of which has its own tag, length, and value.</p>

<p>One of the cool things about DER and other tag-length-value formats is that you
can decode them to some degree without knowing what they mean. For instance, I
can tell you that 0x30 means the data type &ldquo;SEQUENCE&rdquo; (a struct, in ASN.1
terms), and 0x02 means &ldquo;INTEGER&rdquo;, then give you this hex byte sequence to

<pre><code>30 06 02 01 03 02 01 0A

<p>You could tell me right away that decodes to:</p>


<p>Try it yourself with this great <a href="https://lapo.it/asn1js/#300602010302010A">JavaScript ASN.1
decoder</a>. However, you wouldn&rsquo;t know
what those integers represent without the corresponding ASN.1 schema (or
&ldquo;module&rdquo;). For instance, if you knew that this was a piece of DogData, and the
schema was:</p>

<pre><code>DogData ::= SEQUENCE {
cutenessLevel INTEGER

<p>You&rsquo;d know this referred to a three-legged dog with a cuteness level of 10.</p>

<p>We can take some of this knowledge and apply it to our certificates. As a first
step, convert the above certificate to hex with
<code>xxd -ps &lt; Downloads/031f2484307c9bc511b3123cb236a480d451</code>. You can then copy
and paste the result into
<a href="https://lapo.it/asn1js">lapo.it/asn1js</a> (or use <a href="https://lapo.it/asn1js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this handy link</a>). You can also run <code>openssl asn1parse -i -inform der -in Downloads/031f2484307c9bc511b3123cb236a480d451</code> to use OpenSSL&rsquo;s parser, which is less easy to use in some ways, but easier to copy and paste.</p>

<p>In the decoded data, we can find the OID <code></code>, indicating
the SCT list extension. Per <a href="https://tools.ietf.org/html/rfc5280#page-17">RFC 5280, section
4.1</a>, an extension is defined:</p>

<pre><code>Extension ::= SEQUENCE {
— contains the DER encoding of an ASN.1 value
— corresponding to the extension type identified
— by extnID

<p>We&rsquo;ve found the <code>extnID</code>. The &ldquo;critical&rdquo; field is omitted because it has the
default value (false). Next up is the <code>extnValue</code>. This has the type
<code>OCTET STRING</code>, which has the tag &ldquo;0x04&rdquo;. <code>OCTET STRING</code> means &ldquo;here&rsquo;s
a bunch of bytes!&rdquo; In this case, as described by the spec, those bytes
happen to contain more DER. This is a fairly common pattern in X.509
to deal with parameterized data. For instance, this allows defining a
structure for extensions without knowing ahead of time all the structures
that a future extension might want to carry in its value. If you&rsquo;re a C
programmer, think of it as a <code>void*</code> for data structures. If you prefer Go,
think of it as an <code>interface{}</code>.</p>

<p>Here&rsquo;s that <code>extnValue</code>:</p>

<pre><code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

<p>That&rsquo;s tag &ldquo;0x04&rdquo;, meaning <code>OCTET STRING</code>, followed by &ldquo;0x81 0xF5&rdquo;, meaning
&ldquo;this string is 245 bytes long&rdquo; (the 0x81 prefix is part of <a href="#variable-length">variable length
number encoding</a>).</p>

<p>According to <a href="https://tools.ietf.org/html/rfc6962#section-3.3">RFC 6962, section
3.3</a>, &ldquo;obtained SCTs
can be directly embedded in the final certificate, by encoding the
SignedCertificateTimestampList structure as an ASN.1 <code>OCTET STRING</code>
and inserting the resulting data in the TBSCertificate as an X.509v3
certificate extension&rdquo;</p>

<p>So, we have an <code>OCTET STRING</code>, all&rsquo;s good, right? Except if you remove the
tag and length from extnValue to get its value, you&rsquo;re left with:</p>

<pre><code>04 81 F2 00F0007500DB74AFEEC…

<p>There&rsquo;s that &ldquo;0x04&rdquo; tag again, but with a shorter length. Why
do we nest one <code>OCTET STRING</code> inside another? It&rsquo;s because the
contents of extnValue are required by RFC 5280 to be valid DER, but a
SignedCertificateTimestampList is not encoded using DER (more on that
in a minute). So, by RFC 6962, a SignedCertificateTimestampList is wrapped in an
<code>OCTET STRING</code>, which is wrapped in another <code>OCTET STRING</code> (the extnValue).</p>

<p>Once we decode that second <code>OCTET STRING</code>, we&rsquo;re left with the contents:</p>


<p>&ldquo;0x00&rdquo; isn&rsquo;t a valid tag in DER. What is this? It&rsquo;s TLS encoding. This is
defined in <a href="https://tools.ietf.org/html/rfc5246#section-4">RFC 5246, section 4</a>
(the TLS 1.2 RFC). TLS encoding, like ASN.1, has both a way to define data
structures and a way to encode those structures. TLS encoding differs
from DER in that there are no tags, and lengths are only encoded when necessary for
variable-length arrays. Within an encoded structure, the type of a field is determined by
its position, rather than by a tag. This means that TLS-encoded structures are
more compact than DER structures, but also that they can&rsquo;t be processed without
knowing the corresponding schema. For instance, here&rsquo;s the top-level schema from
<a href="https://tools.ietf.org/html/rfc6962#section-3.3">RFC 6962, section 3.3</a>:</p>

<pre><code> The contents of the ASN.1 OCTET STRING embedded in an OCSP extension
or X509v3 certificate extension are as follows:

opaque SerializedSCT&lt;1..2^16-1&gt;;

struct {
SerializedSCT sct_list &lt;1..2^16-1&gt;;
} SignedCertificateTimestampList;

Here, &quot;SerializedSCT&quot; is an opaque byte string that contains the
serialized TLS structure.

<p>Right away, we&rsquo;ve found one of those variable-length arrays. The length of such
an array (in bytes) is always represented by a length field just big enough to
hold the max array size. The max size of an <code>sct_list</code> is 65535 bytes, so the
length field is two bytes wide. Sure enough, those first two bytes are &ldquo;0x00
0xF0&rdquo;, or 240 in decimal. In other words, this <code>sct_list</code> will have 240 bytes. We
don&rsquo;t yet know how many SCTs will be in it. That will become clear only by
continuing to parse the encoded data and seeing where each struct ends (spoiler
alert: there are two SCTs!).</p>

<p>Now we know the first SerializedSCT starts with <code>0075…</code>. SerializedSCT
is itself a variable-length field, this time containing <code>opaque</code> bytes (much like <code>OCTET STRING</code>
back in the ASN.1 world). Like SignedCertificateTimestampList, it has a max size
of 65535 bytes, so we pull off the first two bytes and discover that the first
SerializedSCT is 0x0075 (117 decimal) bytes long. Here&rsquo;s the whole thing, in


<p>This can be decoded using the TLS encoding struct defined in <a href="https://tools.ietf.org/html/rfc6962#page-13">RFC 6962, section

<pre><code>enum { v1(0), (255) }

struct {
opaque key_id[32];
} LogID;

opaque CtExtensions&lt;0..2^16-1&gt;;

struct {
Version sct_version;
LogID id;
uint64 timestamp;
CtExtensions extensions;
digitally-signed struct {
Version sct_version;
SignatureType signature_type = certificate_timestamp;
uint64 timestamp;
LogEntryType entry_type;
select(entry_type) {
case x509_entry: ASN.1Cert;
case precert_entry: PreCert;
} signed_entry;
CtExtensions extensions;
} SignedCertificateTimestamp;

<p>Breaking that down:</p>

<pre><code># Version sct_version v1(0)
# LogID id (aka opaque key_id[32])
# uint64 timestamp (milliseconds since the epoch)
# CtExtensions extensions (zero-length array)
# digitally-signed struct

<p>To understand the &ldquo;digitally-signed struct,&rdquo; we need to turn back to <a href="https://tools.ietf.org/html/rfc5246#section-4.7">RFC 5246,
section 4.7</a>. It says:</p>

<pre><code>A digitally-signed element is encoded as a struct DigitallySigned:

struct {
SignatureAndHashAlgorithm algorithm;
opaque signature&lt;0..2^16-1&gt;;
} DigitallySigned;

<p>And in <a href="https://tools.ietf.org/html/rfc5246#section-">section</a>:</p>

<pre><code>enum {
none(0), md5(1), sha1(2), sha224(3), sha256(4), sha384(5),
sha512(6), (255)
} HashAlgorithm;

enum { anonymous(0), rsa(1), dsa(2), ecdsa(3), (255) }

struct {
HashAlgorithm hash;
SignatureAlgorithm signature;
} SignatureAndHashAlgorithm;

<p>We have &ldquo;0x0403&rdquo;, which corresponds to sha256(4) and ecdsa(3). The next two
bytes, &ldquo;0x0046&rdquo;, tell us the length of the &ldquo;opaque signature&rdquo; field, 70 bytes in
decimal. To decode the signature, we reference <a href="https://tools.ietf.org/html/rfc4492#page-20">RFC 4492 section
5.4</a>, which says:</p>

<pre><code>The digitally-signed element is encoded as an opaque vector &lt;0..2^16-1&gt;, the
contents of which are the DER encoding corresponding to the
following ASN.1 notation.

Ecdsa-Sig-Value ::= SEQUENCE {

<p>Having dived through two layers of TLS encoding, we are now back in ASN.1 land!
<a href="https://lapo.it/asn1js/#304402207E1FCD1E9A2BD2A50A0C81E713033A0762340DA8F91EF27A48B3817640159CD30220659FE9F1D880E2E8F6B325BE9F18956D17C6CA8A6F2B12CB0F55FB70F759A419">decode</a>
the remaining bytes into a SEQUENCE containing two INTEGERS. And we&rsquo;re done! Here&rsquo;s the whole
extension decoded:</p>

<pre><code># Extension SEQUENCE – RFC 5280
# length 0x0104 bytes (260 decimal)
# length 0x0A bytes (10 decimal)
# value (
# length 0xF5 bytes (245 decimal)
# OCTET STRING (embedded) – RFC 6962
# length 0xF2 bytes (242 decimal)
# Beginning of TLS encoded SignedCertificateTimestampList – RFC 5246 / 6962
# length 0xF0 bytes
# opaque SerializedSCT&lt;1..2^16-1&gt;
# length 0x75 bytes
# Version sct_version v1(0)
# LogID id (aka opaque key_id[32])
# uint64 timestamp (milliseconds since the epoch)
# CtExtensions extensions (zero-length array)
# digitally-signed struct – RFC 5426
# SignatureAndHashAlgorithm (ecdsa-sha256)
# opaque signature&lt;0..2^16-1&gt;;
# length 0x0046
# DER-encoded Ecdsa-Sig-Value – RFC 4492
44 # length 0x44 bytes
02 # r INTEGER
20 # length 0x20 bytes
# value
02 # s INTEGER
20 # length 0x20 bytes
# value
# opaque SerializedSCT&lt;1..2^16-1&gt;
# length 0x77 bytes
# Version sct_version v1(0)
# LogID id (aka opaque key_id[32])
# uint64 timestamp (milliseconds since the epoch)
# CtExtensions extensions (zero-length array)
# digitally-signed struct – RFC 5426
# SignatureAndHashAlgorithm (ecdsa-sha256)
# opaque signature&lt;0..2^16-1&gt;;
# length 0x0048
# DER-encoded Ecdsa-Sig-Value – RFC 4492
46 # length 0x46 bytes
02 # r INTEGER
21 # length 0x21 bytes
# value
02 # s INTEGER
21 # length 0x21 bytes
# value

<p>One surprising thing you might notice: In the first SCT, <code>r</code> and <code>s</code> are twenty
bytes long. In the second SCT, they are both twenty-one bytes long, and have a
leading zero. Integers in DER are two&rsquo;s complement, so if the leftmost bit is
set, they are interpreted as negative. Since <code>r</code> and <code>s</code> are positive, if the
leftmost bit would be a 1, an extra byte has to be added so that the leftmost
bit can be 0.</p>

<p>This is a little taste of what goes into encoding a certificate. I hope it was
informative! If you&rsquo;d like to learn more, I recommend &ldquo;<a href="http://luca.ntop.org/Teaching/Appunti/asn1.html">A Layman&rsquo;s Guide to a
Subset of ASN.1, BER, and DER</a>.&rdquo;</p>

<p><a name="poison"></a>Footnote 1: A &ldquo;poison extension&rdquo; is defined by <a href="https://tools.ietf.org/html/rfc6962#section-3.1">RFC 6962
section 3.1</a>:</p>

<pre><code>The Precertificate is constructed from the certificate to be issued by adding a special
critical poison extension (OID ``, whose
extnValue OCTET STRING contains ASN.1 NULL data (0x05 0x00))

<p>In other words, it&rsquo;s an empty extension whose only purpose is to ensure that
certificate processors will not accept precertificates as valid certificates. The
specification ensures this by setting the &ldquo;critical&rdquo; bit on the extension, which
ensures that code that doesn&rsquo;t recognize the extension will reject the whole
certificate. Code that does recognize the extension specifically as poison
will also reject the certificate.</p>

<p><a name="variable-length"></a>Footnote 2: Lengths from 0-127 are represented by
a single byte (short form). To express longer lengths, more bytes are used (long form).
The high bit (0x80) on the first byte is set to distinguish long form from short
form. The remaining bits are used to express how many more bytes to read for the
length. For instance, 0x81F5 means &ldquo;this is long form because the length is
greater than 127, but there&rsquo;s still only one byte of length (0xF5) to decode.&rdquo;</p>

Git v2.17.0 released

Post Syndicated from corbet original https://lwn.net/Articles/750815/rss

Version 2.17.0 of the Git source-code management system is out. It
includes a long list of relatively minor tweaks. “Since Git 1.7.9,
‘git merge’ defaulted to –no-ff (i.e. even when the side branch being
merged is a descendant of the current commit, create a merge commit instead
of fast-forwarding) when merging a tag object. This was appropriate
default for integrators who pull signed tags from their downstream
contributors, but caused an unnecessary merges when used by downstream
contributors who habitually ‘catch up’ their topic branches with tagged
releases from the upstream. Update ‘git merge’ to default to –no-ff only
when merging a tag object that does *not* sit at its usual place in
refs/tags/ hierarchy, and allow fast-forwarding otherwise, to mitigate the

Tag Amazon EBS Snapshots on Creation and Implement Stronger Security Policies

Post Syndicated from Woo Kim original https://aws.amazon.com/blogs/compute/tag-amazon-ebs-snapshots-on-creation-and-implement-stronger-security-policies/

This blog was contributed by Rucha Nene, Sr. Product Manager for Amazon EBS

AWS customers use tags to track ownership of resources, implement compliance protocols, control access to resources via IAM policies, and drive their cost accounting processes. Last year, we made tagging for Amazon EC2 instances and Amazon EBS volumes easier by adding the ability to tag these resources upon creation. We are now extending this capability to EBS snapshots.

Earlier, you could tag your EBS snapshots only after the resource had been created and sometimes, ended up with EBS snapshots in an untagged state if tagging failed. You also could not control the actions that users and groups could take over specific snapshots, or enforce tighter security policies.

To address these issues, we are making tagging for EBS snapshots more flexible and giving customers more control over EBS snapshots by introducing two new capabilities:

  • Tag on creation for EBS snapshots – You can now specify tags for EBS snapshots as part of the API call that creates the resource or via the Amazon EC2 Console when creating an EBS snapshot.
  • Resource-level permission and enforced tag usage – The CreateSnapshot, DeleteSnapshot, and ModifySnapshotAttrribute API actions now support IAM resource-level permissions. You can now write IAM policies that mandate the use of specific tags when taking actions on EBS snapshots.

Tag on creation

You can now specify tags for EBS snapshots as part of the API call that creates the resources. The resource creation and the tagging are performed atomically; both must succeed in order for the operation CreateSnapshot to succeed. You no longer need to build tagging scripts that run after EBS snapshots have been created.

Here’s how you specify tags when you create an EBS snapshot, using the console:

  1. Open the Amazon EC2 console at https://console.aws.amazon.com/ec2/.
  2. In the navigation pane, choose Snapshots, Create Snapshot.
  3. On the Create Snapshot page, select the volume for which to create a snapshot.
  4. (Optional) Choose Add tags to your snapshot. For each tag, provide a tag key and a tag value.
  5. Choose Create Snapshot.

Using the AWS CLI:

aws ec2 create-snapshot --volume-id vol-0c0e757e277111f3c --description 'Prod_Backup' --tag-specifications 

To learn more, see Using Tags.

Resource-level permissions and enforced tag usage

CreateSnapshot, DeleteSnapshot, and ModifySnapshotAttribute now support resource-level permissions, which allow you to exercise more control over EBS snapshots. You can write IAM policies that give you precise control over access to resources and let you specify which users are able to create snapshots for a given set of volumes. You can also enforce the use of specific tags to help track resources and achieve more accurate cost allocation reporting.

For example, here’s a statement that requires that the costcenter tag (with a value of “115”) be present on the volume from which snapshots are being created. It requires that this tag be applied to all newly created snapshots. In addition, it requires that the created snapshots are tagged with User:username for the customer.

	   "Condition": {

To implement stronger compliance and security policies, you could also restrict access to DeleteSnapshot, if the resource is not tagged with the user’s name. Here’s a statement that allows the deletion of a snapshot only if the snapshot is tagged with User:username for the customer.


To learn more and to see some sample policies, see IAM Policies for Amazon EC2 and Working with Snapshots.

Available Now

These new features are available now in all AWS Regions. You can start using it today from the Amazon EC2 Console, AWS Command Line Interface (CLI), or the AWS APIs.

New – Amazon DynamoDB Continuous Backups and Point-In-Time Recovery (PITR)

Post Syndicated from Randall Hunt original https://aws.amazon.com/blogs/aws/new-amazon-dynamodb-continuous-backups-and-point-in-time-recovery-pitr/

The Amazon DynamoDB team is back with another useful feature hot on the heels of encryption at rest. At AWS re:Invent 2017 we launched global tables and on-demand backup and restore of your DynamoDB tables and today we’re launching continuous backups with point-in-time recovery (PITR).

You can enable continuous backups with a single click in the AWS Management Console, a simple API call, or with the AWS Command Line Interface (CLI). DynamoDB can back up your data with per-second granularity and restore to any single second from the time PITR was enabled up to the prior 35 days. We built this feature to protect against accidental writes or deletes. If a developer runs a script against production instead of staging or if someone fat-fingers a DeleteItem call, PITR has you covered. We also built it for the scenarios you can’t normally predict. You can still keep your on-demand backups for as long as needed for archival purposes but PITR works as additional insurance against accidental loss of data. Let’s see how this works.

Continuous Backup

To enable this feature in the console we navigate to our table and select the Backups tab. From there simply click Enable to turn on the feature. I could also turn on continuous backups via the UpdateContinuousBackups API call.

After continuous backup is enabled we should be able to see an Earliest restore date and Latest restore date

Let’s imagine a scenario where I have a lot of old user profiles that I want to delete.

I really only want to send service updates to our active users based on their last_update date. I decided to write a quick Python script to delete all the users that haven’t used my service in a while.

import boto3
table = boto3.resource("dynamodb").Table("VerySuperImportantTable")
items = table.scan(
    FilterExpression="last_update >= :date",
    ExpressionAttributeValues={":date": "2014-01-01T00:00:00"},
print("Deleting {} Items! Dangerous.".format(len(items)))
with table.batch_writer() as batch:
    for item in items:

Great! This should delete all those pesky non-users of my service that haven’t logged in since 2013. So,— CTRL+C CTRL+C CTRL+C CTRL+C (interrupt the currently executing command).

Yikes! Do you see where I went wrong? I’ve just deleted my most important users! Oh, no! Where I had a greater-than sign, I meant to put a less-than! Quick, before Jeff Barr can see, I’m going to restore the table. (I probably could have prevented that typo with Boto 3’s handy DynamoDB conditions: Attr("last_update").lt("2014-01-01T00:00:00"))


Luckily for me, restoring a table is easy. In the console I’ll navigate to the Backups tab for my table and click Restore to point-in-time.

I’ll specify the time (a few seconds before I started my deleting spree) and a name for the table I’m restoring to.

For a relatively small and evenly distributed table like mine, the restore is quite fast.

The time it takes to restore a table varies based on multiple factors and restore times are not neccesarily coordinated with the size of the table. If your dataset is evenly distributed across your primary keys you’ll be able to take advanatage of parallelization which will speed up your restores.

Learn More & Try It Yourself
There’s plenty more to learn about this new feature in the documentation here.

Pricing for continuous backups varies by region and is based on the current size of the table and all indexes.

A few things to note:

  • PITR works with encrypted tables.
  • If you disable PITR and later reenable it, you reset the start time from which you can recover.
  • Just like on-demand backups, there are no performance or availability impacts to enabling this feature.
  • Stream settings, Time To Live settings, PITR settings, tags, Amazon CloudWatch alarms, and auto scaling policies are not copied to the restored table.
  • Jeff, it turns out, knew I restored the table all along because every PITR API call is recorded in AWS CloudTrail.

Let us know how you’re going to use continuous backups and PITR on Twitter and in the comments.

Tracking Cookies and GDPR

Post Syndicated from Bozho original https://techblog.bozho.net/tracking-cookies-gdpr/

GDPR is the new data protection regulation, as you probably already know. I’ve given a detailed practical advice for what it means for developers (and product owners). However, there’s one thing missing there – cookies. The elephant in the room.

Previously I’ve stated that cookies are subject to another piece of legislation – the ePrivacy directive, which is getting updated and its new version will be in force a few years from now. And while that’s technically correct, cookies seem to be affected by GDPR as well. In a way I’ve underestimated that effect.

When you do a Google search on “GDPR cookies”, you’ll pretty quickly realize that a) there’s not too much information and b) there’s not much technical understanding of the issue.

What appears to be the consensus is that GDPR does change the way cookies are handled. More specifically – tracking cookies. Here’s recital 30:

(30) Natural persons may be associated with online identifiers provided by their devices, applications, tools and protocols, such as internet protocol addresses, cookie identifiers or other identifiers such as radio frequency identification tags. This may leave traces which, in particular when combined with unique identifiers and other information received by the servers, may be used to create profiles of the natural persons and identify them.

How tracking cookies work – a 3rd party (usually an ad network) gives you a code snippet that you place on your website, for example to display ads. That code snippet, however, calls “home” (makes a request to the 3rd party domain). If the 3rd party has previously been used on your computer, it has created a cookie. In the example of Facebook, they have the cookie with your Facebook identifier because you’ve logged in to Facebook. So this cookie (with your identifier) is sent with the request. The request also contains all the details from the page. In effect, you are uniquely identified by an identifier (in the case of Facebook and Google – fully identified, rather than some random anonymous identifier as with other ad networks).

Your behaviour on the website is personal data. It gets associated with your identifier, which in turn is associated with your profile. And all of that is personal data. Who is responsible for collecting the website behaviour data, i.e. who is the “controller”? Is it Facebook (or any other 3rd party) that technically does the collection? No, it’s the website owner, as the behaviour data is obtained on their website, and they have put the tracking piece of code there. So they bear responsibility.

What’s the responsibility? So far it boiled down to displaying the useless “we use cookies” warning that nobody cares about. And the current (old) ePrivacy directive and its interpretations says that this is enough – if the users actions can unambiguously mean that they are fine with cookies – i.e. if they continue to use the website after seeing the warning – then you’re fine. This is no longer true from a GDPR perspective – you are collecting user data and you have to have a lawful ground for processing.

For the data collected by tracking cookies you have two options – “consent” and “legitimate interest”. Legitimate interest will be hard to prove – it is not something that a user reasonably expects, it is not necessary for you to provide the service. If your lawyers can get that option to fly, good for them, but I’m not convinced regulators will be happy with that.

The other option is “consent”. You have to ask your users explicitly – that means “with a checkbox” – to let you use tracking cookies. That has two serious implications – from technical and usability point of view.

  • The technical issue is that the data is sent via 3rd party code as soon as the page loads and before the user can give their consent. And that’s already a violation. You can, of course, have the 3rd party code be dynamically inserted only after the user gives consent, but that will require some fiddling with javascript and might not always work depending on the provider. And you’d have to support opt-out at any time (which would in turn disable the 3rd party snippet). It would require actual coding, rather than just copy-pasting a snippet.
  • The usability aspect is the bigger issue – while you could neatly tuck a cookie warning at the bottom, you’d now have to have a serious, “stop the world” popup that asks for consent if you want anyone to click it. You can, of course, just add a checkbox to the existing cookie warning, but don’t expect anyone to click it.

These aspects pose a significant questions: is it worth it to have tracking cookies? Is developing new functionality worth it, is interrupting the user worth it, and is implementing new functionality just so that users never clicks a hidden checkbox worth it? Especially given that Firefox now blocks all tracking cookies and possibly other browsers will follow?

That by itself is an interesting topic – Firefox has basically implemented the most strict form of requirements of the upcoming ePrivacy directive update (that would turn it into an ePrivacy regulation). Other browsers will have to follow, even though Google may not be happy to block their own tracking cookies. I hope other browsers follow Firefox in tracking protection and the issue will be gone automatically.

To me it seems that it will be increasingly not worthy to have tracking cookies on your website. They add regulatory obligations for you and give you very little benefit (yes, you could track engagement from ads, but you can do that in other ways, arguably by less additional code than supporting the cookie consents). And yes, the cookie consent will be “outsourced” to browsers after the ePrivacy regulation is passed, but we can’t be sure at the moment whether there won’t be technical whack-a-mole between browsers and advertisers and whether you wouldn’t still need additional effort to have dynamic consent for tracking cookies. (For example there are reported issues that Firefox used to make Facebook login fail if tracking protection is enabled. Which could be a simple bug, or could become a strategy by big vendors in the future to force browsers into a less strict tracking protection).

Okay, we’ve decided it’s not worth it managing tracking cookies. But do you have a choice as a website owner? Can you stop your ad network from using them? (Remember – you are liable if users’ data is collected by visiting your website). And currently the answer is no – you can’t disable that. You can’t have “just the ads”. This is part of the “deal” – you get money for the ads you place, but you participate in a big “surveillance” network. Users have a way to opt out (e.g. Google AdWords gives them that option). You, as a website owner, don’t.

Facebook has a recommendations page that says “you take care of getting the consent”. But for example the “like button” plugin doesn’t have an option to not send any data to Facebook.

And sometimes you don’t want to serve ads, just track user behaviour and measure conversion. But even if you ask for consent for that and conditionally insert the plugin/snippet, do you actually know what data it sends? And what it’s used for? Because you have to know in order to inform your users. “Do you agree to use tracking cookies that Facebook has inserted in order to collect data about your behaviour on our website” doesn’t sound compelling.

So, what to do? The easiest thing is just not to use any 3rd party ad-related plugins. But that’s obviously not an option, as ad revenue is important, especially in the publishing industry. I don’t have a good answer, apart from “Regulators should pressure ad networks to provide opt-outs and clearly document their data usage”. They have to do that under GDPR, and while website owners are responsible for their users’ data, the ad networks that are in the role of processors in this case (as you delegate the data collection for your visitors to them) also have obligation to assist you in fulfilling your obligations. So ask Facebook – what should I do with your tracking cookies? And when the regulator comes after a privacy-aware customer files a complaint, you could prove that you’ve tried.

The ethical debate whether it’s wrong to collect data about peoples’ behaviour without their informed consent is an easy one. And that’s why I don’t put blame on the regulators – they are putting the ethical consensus in law. It gets more complicated if not allowing tracking means some internet services are no longer profitable and therefore can’t exist. Can we have the cake and eat it too?

The post Tracking Cookies and GDPR appeared first on Bozho's tech blog.

How The Pirate Bay Helped Spotify Become a Success

Post Syndicated from Ernesto original https://torrentfreak.com/how-the-pirate-bay-helped-spotify-become-a-success-180319/

When Spotify launched its first beta in the fall of 2008, many people were blown away by its ease of use.

With the option to stream millions of tracks supported by an occasional ad, or free of ads for a small subscription fee, Spotify offered something that was more convenient than piracy.

In the years that followed, Spotify rolled out its music service in more than 60 countries, amassing over 160 million users. While the service is often billed as a piracy killer, ironically, it also owes its success to piracy.

As a teenager, Spotify founder and CEO Daniel Ek was fascinated by Napster, which triggered a piracy revolution in the late nineties. Napster made all the music in the world accessible in a few clicks, something Spotify also set out to do a few years later, legally.

“I want to replicate my first experience with piracy,” Ek told Businessweek years ago. “What eventually killed it was that it didn’t work for the people participating with the content. The challenge here is about solving both of those things.”

While the technical capabilities were certainly there, the main stumbling block was getting the required licenses. The music industry hadn’t had a lot of good experiences with the Internet a decade ago so there was plenty of hesitation.

The same was true of Sweden, where The Pirate Bay had just gained a lot of traction. There was a pro-sharing culture being cultivated by Piratbyrån, Swedish for the Piracy Bureau, which was the driving force behind the torrent site in the early days.

After the first Pirate Bay raid in 2006, thousands of people gathered in the streets of Stockholm to declare their support for the site and their right to share.

Pro-piracy protest in Stockholm (Jon Åslund, CC BY 2.5)

Interestingly, however, this pro-piracy climate turned out to be in Spotify’s favor. In a detailed feature in the Swedish newspaper Breakit Per Sundin, CEO of Sony BMG at the time, suggests that The Pirate Bay helped Spotify.

“If Pirate Bay had not existed or made such a mess in the market, I don’t think Spotify would have seen the light of the day. You wouldn’t get the licenses you wanted,” Sundin said.

With music industry revenues dropping, record labels had to fire hundreds of people. They were becoming desperate and were looking for change, something Spotify was promising.

At the time, the idea of having millions of songs readily and legally available was totally new. Many immediately saw it as an “alternative to music piracy” and even Pirate Bay founder Peter Sunde was impressed.

“It was great. It was always what was missing in the pirate services, that intuitive interface,” Sunde told Breakit.

Sunde also believed that The Pirate Bay and all the buzz around piracy in Sweden was a great boon to Spotify. But while the latter turned into a billion-dollar business that’s about to go public, Sunde and the other TPB founders still owe the labels millions in damages.

“Without file-sharing, The Pirate Bay and the political work done by Piratbyrån, it was not possible to get the licensing agreements Spotify received,” Sunde said. “Sometimes I think I should have received 10, 20 or 30 percent of Spotify, as a thank you for the help.”

In addition to creating the right climate for the major record labels to get on board, The Pirate Bay also appears to have been of more practical assistance.

When Spotify first launched several people noticed that some tracks still had tags from pirate groups such as FairLight in the title. Those are not the files you expect the labels to offer, but files that were on The Pirate Bay.

Also, Spotify mysteriously offered music from a band that decided to share their music on The Pirate Bay, instead of the usual outlets. There’s only one place that could have originated from.

The Pirate Bay.

Source: TF, for the latest info on copyright, file-sharing, torrent sites and more. We also have VPN reviews, discounts, offers and coupons.

Central Logging in Multi-Account Environments

Post Syndicated from matouk original https://aws.amazon.com/blogs/architecture/central-logging-in-multi-account-environments/

Centralized logging is often required in large enterprise environments for a number of reasons, ranging from compliance and security to analytics and application-specific needs.

I’ve seen that in a multi-account environment, whether the accounts belong to the same line of business or multiple business units, collecting logs in a central, dedicated logging account is an established best practice. It helps security teams detect malicious activities both in real-time and during incident response. It provides protection to log data in case it is accidentally or intentionally deleted. It also helps application teams correlate and analyze log data across multiple application tiers.

This blog post provides a solution and building blocks to stream Amazon CloudWatch log data across accounts. In a multi-account environment this repeatable solution could be deployed multiple times to stream all relevant Amazon CloudWatch log data from all accounts to a centralized logging account.

Solution Summary 

The solution uses Amazon Kinesis Data Streams and a log destination to set up an endpoint in the logging account to receive streamed logs and uses Amazon Kinesis Data Firehose to deliver log data to the Amazon Simple Storage Solution (S3) bucket. Application accounts will subscribe to stream all (or part) of their Amazon CloudWatch logs to a defined destination in the logging account via subscription filters.

Below is a diagram illustrating how the various services work together.

In logging an account, a Kinesis Data Stream is created to receive streamed log data and a log destination is created to facilitate remote streaming, configured to use the Kinesis Data Stream as its target.

The Amazon Kinesis Data Firehose stream is created to deliver log data from the data stream to S3. The delivery stream uses a generic AWS Lambda function for data validation and transformation.

In each application account, a subscription filter is created between each Amazon CloudWatch log group and the destination created for this log group in the logging account.

The following steps are involved in setting up the central-logging solution:

  1. Create an Amazon S3 bucket for your central logging in the logging account
  2. Create an AWS Lambda function for log data transformation and decoding in logging account
  3. Create a central logging stack as a logging-account destination ready to receive streamed logs and deliver them to S3
  4. Create a subscription in application accounts to deliver logs from a specific CloudWatch log group to the logging account destination
  5. Create Amazon Athena tables to query and analyze log data in your logging account

Creating a log destination in your logging account

In this section, we will setup the logging account side of the solution, providing detail on the list above. The example I use is for the us-east-1 region, however any region where required services are available could be used.

It’s important to note that your logging-account destination and application-account subscription must be in the same region. You can deploy the solution multiple times to create destinations in all required regions if application accounts use multiple regions.

Step 1: Create an S3 bucket

Use the CloudFormation template below to create S3 bucket in logging account. This template also configures the bucket to archive log data to Glacier after 60 days.

  "Description": "CF Template to create S3 bucket for central logging",

      "Description":"Central logging bucket name"
   "CentralLoggingBucket" : {
      "Type" : "AWS::S3::Bucket",
      "Properties" : {
        "BucketName" : {"Ref": "BucketName"},
        "LifecycleConfiguration": {
            "Rules": [
                  "Id": "ArchiveToGlacier",
                  "Prefix": "",
                  "Status": "Enabled",
                      "TransitionInDays": "60",
                      "StorageClass": "GLACIER"

    	"Description" : "Central log bucket",
    	"Value" : {"Ref": "BucketName"} ,
    	"Export" : { "Name" : "CentralLogBucketName"}

To create your central-logging bucket do the following:

  1. Save the template file to your local developer machine as “central-log-bucket.json”
  2. From the CloudFormation console, select “create new stack” and import the file “central-log-bucket.json”
  3. Fill in the parameters and complete stack creation steps (as indicated in the screenshot below)
  4. Verify the bucket has been created successfully and take a note of the bucket name

Step 2: Create data processing Lambda function

Use the template below to create a Lambda function in your logging account that will be used by Amazon Firehose for data transformation during the delivery process to S3. This function is based on the AWS Lambda kinesis-firehose-cloudwatch-logs-processor blueprint.

The function could be created manually from the blueprint or using the cloudformation template below. To find the blueprint navigate to Lambda -> Create -> Function -> Blueprints

This function will unzip the event message, parse it and verify that it is a valid CloudWatch log event. Additional processing can be added if needed. As this function is generic, it could be reused by all log-delivery streams.

  "Description": "Create cloudwatch data processing lambda function",
    "LambdaRole": {
        "Type": "AWS::IAM::Role",
        "Properties": {
            "AssumeRolePolicyDocument": {
                "Version": "2012-10-17",
                "Statement": [
                        "Effect": "Allow",
                        "Principal": {
                            "Service": "lambda.amazonaws.com"
                        "Action": "sts:AssumeRole"
            "Path": "/",
            "Policies": [
                    "PolicyName": "firehoseCloudWatchDataProcessing",
                    "PolicyDocument": {
                        "Version": "2012-10-17",
                        "Statement": [
                                "Effect": "Allow",
                                "Action": [
                                "Resource": "arn:aws:logs:*:*:*"
    "FirehoseDataProcessingFunction": {
        "Type": "AWS::Lambda::Function",
        "Properties": {
            "Handler": "index.handler",
            "Role": {"Fn::GetAtt": ["LambdaRole","Arn"]},
            "Description": "Firehose cloudwatch data processing",
            "Code": {
                "ZipFile" : { "Fn::Join" : ["\n", [
                  "'use strict';",
                  "const zlib = require('zlib');",
                  "function transformLogEvent(logEvent) {",
                  "       return Promise.resolve(`${logEvent.message}\n`);",
                  "exports.handler = (event, context, callback) => {",
                  "    Promise.all(event.records.map(r => {",
                  "        const buffer = new Buffer(r.data, 'base64');",
                  "        const decompressed = zlib.gunzipSync(buffer);",
                  "        const data = JSON.parse(decompressed);",
                  "        if (data.messageType !== 'DATA_MESSAGE') {",
                  "            return Promise.resolve({",
                  "                recordId: r.recordId,",
                  "                result: 'ProcessingFailed',",
                  "            });",
                  "         } else {",
                  "            const promises = data.logEvents.map(transformLogEvent);",
                  "            return Promise.all(promises).then(transformed => {",
                  "                const payload = transformed.reduce((a, v) => a + v, '');",
                  "                const encoded = new Buffer(payload).toString('base64');",
                  "                console.log('---------------payloadv2:'+JSON.stringify(payload, null, 2));",
                  "                return {",
                  "                    recordId: r.recordId,",
                  "                    result: 'Ok',",
                  "                    data: encoded,",
                  "                };",
                  "           });",
                  "        }",
                  "    })).then(recs => callback(null, { records: recs }));",

            "Runtime": "nodejs6.10",
            "Timeout": "60"

   "Function" : {
      "Description": "Function ARN",
      "Value": {"Fn::GetAtt": ["FirehoseDataProcessingFunction","Arn"]},
      "Export" : { "Name" : {"Fn::Sub": "${AWS::StackName}-Function" }}

To create the function follow the steps below:

  1. Save the template file as “central-logging-lambda.json”
  2. Login to logging account and, from the CloudFormation console, select “create new stack”
  3. Import the file “central-logging-lambda.json” and click next
  4. Follow the steps to create the stack and verify successful creation
  5. Take a note of Lambda function arn from the output section

Step 3: Create log destination in logging account

Log destination is used as the target of a subscription from application accounts, log destination can be shared between multiple subscriptions however according to the architecture suggested in this solution all logs streamed to the same destination will be stored in the same S3 location, if you would like to store log data in different hierarchy or in a completely different bucket you need to create separate destinations.

As noted previously, your destination and subscription have to be in the same region

Use the template below to create destination stack in logging account.

  "Description": "Create log destination and required resources",

      "Description":"Destination logging bucket"
      "Description":"S3 location for the logs streamed to this destination; example marketing/prod/999999999999/flow-logs/"
      "Description":"CloudWatch logs data processing function"
      "Description":"Source application account number"
    "MyStream": {
      "Type": "AWS::Kinesis::Stream",
      "Properties": {
        "Name": {"Fn::Join" : [ "", [{ "Ref" : "AWS::StackName" },"-Stream"] ]},
        "RetentionPeriodHours" : 48,
        "ShardCount": 1,
        "Tags": [
            "Key": "Solution",
            "Value": "CentralLogging"
    "LogRole" : {
      "Type"  : "AWS::IAM::Role",
      "Properties" : {
          "AssumeRolePolicyDocument" : {
              "Statement" : [ {
                  "Effect" : "Allow",
                  "Principal" : {
                      "Service" : [ {"Fn::Join": [ "", [ "logs.", { "Ref": "AWS::Region" }, ".amazonaws.com" ] ]} ]
                  "Action" : [ "sts:AssumeRole" ]
              } ]
          "Path" : "/service-role/"
    "LogRolePolicy" : {
        "Type" : "AWS::IAM::Policy",
        "Properties" : {
            "PolicyName" : {"Fn::Join" : [ "", [{ "Ref" : "AWS::StackName" },"-LogPolicy"] ]},
            "PolicyDocument" : {
              "Version": "2012-10-17",
              "Statement": [
                  "Effect": "Allow",
                  "Action": ["kinesis:PutRecord"],
                  "Resource": [{ "Fn::GetAtt" : ["MyStream", "Arn"] }]
                  "Effect": "Allow",
                  "Action": ["iam:PassRole"],
                  "Resource": [{ "Fn::GetAtt" : ["LogRole", "Arn"] }]
            "Roles" : [ { "Ref" : "LogRole" } ]
    "LogDestination" : {
      "Type" : "AWS::Logs::Destination",
      "DependsOn" : ["MyStream","LogRole","LogRolePolicy"],
      "Properties" : {
        "DestinationName": {"Fn::Join" : [ "", [{ "Ref" : "AWS::StackName" },"-Destination"] ]},
        "RoleArn": { "Fn::GetAtt" : ["LogRole", "Arn"] },
        "TargetArn": { "Fn::GetAtt" : ["MyStream", "Arn"] },
        "DestinationPolicy": { "Fn::Join" : ["",[
				"{\"Version\" : \"2012-10-17\",\"Statement\" : [{\"Effect\" : \"Allow\",",
                " \"Principal\" : {\"AWS\" : \"", {"Ref":"SourceAccount"} ,"\"},",
                "\"Action\" : \"logs:PutSubscriptionFilter\",",
                " \"Resource\" : \"", 
                {"Fn::Join": [ "", [ "arn:aws:logs:", { "Ref": "AWS::Region" }, ":" ,{ "Ref": "AWS::AccountId" }, ":destination:",{ "Ref" : "AWS::StackName" },"-Destination" ] ]}  ,"\"}]}"

    "S3deliveryStream": {
      "DependsOn": ["S3deliveryRole", "S3deliveryPolicy"],
      "Type": "AWS::KinesisFirehose::DeliveryStream",
      "Properties": {
        "DeliveryStreamName": {"Fn::Join" : [ "", [{ "Ref" : "AWS::StackName" },"-DeliveryStream"] ]},
        "DeliveryStreamType": "KinesisStreamAsSource",
        "KinesisStreamSourceConfiguration": {
            "KinesisStreamARN": { "Fn::GetAtt" : ["MyStream", "Arn"] },
            "RoleARN": {"Fn::GetAtt" : ["S3deliveryRole", "Arn"] }
        "ExtendedS3DestinationConfiguration": {
          "BucketARN": {"Fn::Join" : [ "", ["arn:aws:s3:::",{"Ref":"LogBucketName"}] ]},
          "BufferingHints": {
            "IntervalInSeconds": "60",
            "SizeInMBs": "50"
          "CompressionFormat": "UNCOMPRESSED",
          "Prefix": {"Ref": "LogS3Location"},
          "RoleARN": {"Fn::GetAtt" : ["S3deliveryRole", "Arn"] },
          "ProcessingConfiguration" : {
              "Enabled": "true",
              "Processors": [
                "Parameters": [ 
                    "ParameterName": "LambdaArn",
                    "ParameterValue": {"Ref":"ProcessingLambdaARN"}
                "Type": "Lambda"

    "S3deliveryRole": {
      "Type": "AWS::IAM::Role",
      "Properties": {
        "AssumeRolePolicyDocument": {
          "Version": "2012-10-17",
          "Statement": [
              "Sid": "",
              "Effect": "Allow",
              "Principal": {
                "Service": "firehose.amazonaws.com"
              "Action": "sts:AssumeRole",
              "Condition": {
                "StringEquals": {
                  "sts:ExternalId": {"Ref":"AWS::AccountId"}
    "S3deliveryPolicy": {
      "Type": "AWS::IAM::Policy",
      "Properties": {
        "PolicyName": {"Fn::Join" : [ "", [{ "Ref" : "AWS::StackName" },"-FirehosePolicy"] ]},
        "PolicyDocument": {
          "Version": "2012-10-17",
          "Statement": [
              "Effect": "Allow",
              "Action": [
              "Resource": [
                {"Fn::Join": ["", [ {"Fn::Join" : [ "", ["arn:aws:s3:::",{"Ref":"LogBucketName"}] ]}]]},
                {"Fn::Join": ["", [ {"Fn::Join" : [ "", ["arn:aws:s3:::",{"Ref":"LogBucketName"}] ]}, "*"]]}
              "Effect": "Allow",
              "Action": [
              "Resource": "*"
        "Roles": [{"Ref": "S3deliveryRole"}]

   "Destination" : {
      "Description": "Destination",
      "Value": {"Fn::Join": [ "", [ "arn:aws:logs:", { "Ref": "AWS::Region" }, ":" ,{ "Ref": "AWS::AccountId" }, ":destination:",{ "Ref" : "AWS::StackName" },"-Destination" ] ]},
      "Export" : { "Name" : {"Fn::Sub": "${AWS::StackName}-Destination" }}


To create log your destination and all required resources, follow these steps:

  1. Save your template as “central-logging-destination.json”
  2. Login to your logging account and, from the CloudFormation console, select “create new stack”
  3. Import the file “central-logging-destination.json” and click next
  4. Fill in the parameters to configure the log destination and click Next
  5. Follow the default steps to create the stack and verify successful creation
    1. Bucket name is the same as in the “create central logging bucket” step
    2. LogS3Location is the directory hierarchy for saving log data that will be delivered to this destination
    3. ProcessingLambdaARN is as created in “create data processing Lambda function” step
    4. SourceAccount is the application account number where the subscription will be created
  6. Take a note of destination ARN as it appears in outputs section as you did above.

Step 4: Create the log subscription in your application account

In this section, we will create the subscription filter in one of the application accounts to stream logs from the CloudWatch log group to the log destination that was created in your logging account.

Create log subscription filter

The subscription filter is created between the CloudWatch log group and a destination endpoint. Asubscription could be filtered to send part (or all) of the logs in the log group. For example,you can create a subscription filter to stream only flow logs with status REJECT.

Use the CloudFormation template below to create subscription filter. Subscription filter and log destination must be in the same region.

  "Description": "Create log subscription filter for a specific Log Group",

      "Description":"ARN of logs destination"
      "Description":"Name of LogGroup to forward logs from"
      "Description":"Filter pattern to filter events to be sent to log destination; Leave empty to send all logs"
    "SubscriptionFilter" : {
      "Type" : "AWS::Logs::SubscriptionFilter",
      "Properties" : {
        "LogGroupName" : { "Ref" : "LogGroupName" },
        "FilterPattern" : { "Ref" : "FilterPattern" },
        "DestinationArn" : { "Ref" : "DestinationARN" }

To create a subscription filter for one of CloudWatch log groups in your application account, follow the steps below:

  1. Save the template as “central-logging-subscription.json”
  2. Login to your application account and, from the CloudFormation console, select “create new stack”
  3. Select the file “central-logging-subscription.json” and click next
  4. Fill in the parameters as appropriate to your environment as you did above
    a.  DestinationARN is the value of obtained in “create log destination in logging account” step
    b.  FilterPatterns is the filter value for log data to be streamed to your logging account (leave empty to stream all logs in the selected log group)
    c.  LogGroupName is the log group as it appears under CloudWatch Logs
  5. Verify successful creation of the subscription

This completes the deployment process in both the logging- and application-account side. After a few minutes, log data will be streamed to the central-logging destination defined in your logging account.

Step 5: Analyzing log data

Once log data is centralized, it opens the door to run analytics on the consolidated data for business or security reasons. One of the powerful services that AWS offers is Amazon Athena.

Amazon Athena allows you to query data in S3 using standard SQL.

Follow the steps below to create a simple table and run queries on the flow logs data that has been collected from your application accounts

  1. Login to your logging account and from the Amazon Athena console, use the DDL below in your query  editor to create a new table


Version INT,

Account STRING,

InterfaceId STRING,

SourceAddress STRING,

DestinationAddress STRING,

SourcePort INT,

DestinationPort INT,

Protocol INT,

Packets INT,

Bytes INT,

StartTime INT,

EndTime INT,

Action STRING,

LogStatus STRING


ROW FORMAT SERDE ‘org.apache.hadoop.hive.serde2.RegexSerDe’


“input.regex” = “^([^ ]+)\\s+([0-9]+)\\s+([^ ]+)\\s+([^ ]+)\\s+([^ ]+)\\s+([^ ]+)\\s+([^ ]+)\\s+([^ ]+)\\s+([^ ]+)\\s+([^ ]+)\\s+([0-9]+)\\s+([0-9]+)\\s+([^ ]+)\\s+([^ ]+)$”)

LOCATION ‘s3://central-logging-company-do-not-delete/’;

2. Click ”run query” and verify a successful run/ This creates the table “prod_vpc_flow_logs”

3. You can then run queries against the table data as below:


By following the steps I’ve outlined, you will build a central logging solution to stream CloudWatch logs from one application account to a central logging account. This solution is repeatable and could be deployed multiple times for multiple accounts and logging requirements.


About the Author

Mahmoud Matouk is a Senior Cloud Infrastructure Architect. He works with our customers to help accelerate migration and cloud adoption at the enterprise level.


Grafana v5.0 Released

Post Syndicated from Blogs on Grafana Labs Blog original https://grafana.com/blog/2018/03/01/grafana-v5.0-released/

v5.0 Stable Released

We have been working on Grafana v5 for most of 2017 and it’s finally ready! This release is important
in a different way than previous releases as main focus has been on improving the core Grafana features and attributes.
That means vastly improved UX and page design, easier and more flexible dashboard building enabled by a
new grid layout system. Better support for large installations with the addition of Dashboard Folders, Teams and Permissions.
Improvements to provisioning/cloud-native setups by making datasources & dashboards configurable from files.

This is the most substantial update that Grafana has ever seen.

Download Grafana 5.0 Now

What’s New in Grafana v5.0

Video showing new features

New Dashboard Layout Engine

The new dashboard layout engine allows for much easier movement and sizing of panels, as other panels now move out of the way in
a very intuitive way. Panels are sized independently, so rows are no longer necessary to create layouts. This opens
up many new types of layouts where panels of different heights can be aligned easily. Checkout the new grid in the video
above or on the play site. All your existing dashboards will automatically migrate to the
new position system and look close to identical. The new panel position makes dashboards saved in v5.0 incompatible
with older versions of Grafana.

New UX

Almost every page has seen significant UX improvements. All pages (except dashboard pages) have a new tab-based layout that improves navigation between pages. The side menu has also changed quite a bit. You can still hide the side menu completely if you click on the Grafana logo.

Dashboard Settings

Dashboard pages have a new header toolbar where buttons and actions are now all moved to the right. All the dashboard
settings views have been combined with a side nav which allows you to easily move between different setting categories.

New Light Theme

This theme has not seen a lot of love in recent years and we felt it was time to give it a major overhaul. We are very happy with the result.

Dashboard Folders

The big new feature that comes with Grafana v5.0 is dashboard folders. Now you can organize your dashboards in folders,
which is very useful if you have a lot of dashboards or multiple teams.

  • New search design adds expandable sections for each folder, starred and recently viewed dashboards.
  • New manage dashboard pages enable batch actions and views for folder settings and permissions.
  • Set permissions on folders and have dashboards inherit the permissions.


A team is a new concept in Grafana v5. They are simply a group of users that can be used in the new permission system for dashboards and folders. Only an admin can create teams.
We hope to do more with teams in future releases like integration with LDAP and a team landing page.


You can assign permissions to folders and dashboards. The default user role-based permissions can be removed and
replaced with specific teams or users enabling more control over what a user can see and edit.

Dashboard permissions only limits what dashboards & folders a user can view & edit not which
data sources a user can access nor what queries a user can issue.

Provisioning from configuration

In previous versions of Grafana, you could only use the API for provisioning data sources and dashboards.
But that required the service to be running before you started creating dashboards and you also needed to
set up credentials for the HTTP API. In v5.0 we decided to improve this experience by adding a new active
provisioning system that uses config files. This will make GitOps more natural as data sources and dashboards can
be defined via files that can be version controlled. We hope to extend this system to later add support for users, orgs
and alerts as well.

Data sources

Data sources can now be setup using config files. These data sources are by default not editable from the Grafana GUI.
It’s also possible to update and delete data sources from the config file. More info in the data source provisioning docs.


We also deprecated the [dashboard.json] in favor of our new dashboard provisioner that keeps dashboards on disk
in sync with dashboards in Grafana’s database. The dashboard provisioner has multiple advantages over the old
[dashboard.json] feature. Instead of storing the dashboard in memory we now insert the dashboard into the database,
which makes it possible to star them, use one as the home dashboard, set permissions and other features in Grafana that
expects the dashboards to exist in the database. More info in the dashboard provisioning docs

Graphite Tags & Integrated Function Docs

The Graphite query editor has been updated to support the latest Graphite version (v1.1) that adds
many new functions and support for querying by tags. You can now also view function documentation right in the query editor!

Read more on Graphite Tag Support.


Checkout the CHANGELOG.md file for a complete list
of new features, changes, and bug fixes.


Head to download page for download links & instructions.


A big thanks to all the Grafana users who contribute by submitting PRs, bug reports & feedback!

How to Patch Linux Workloads on AWS

Post Syndicated from Koen van Blijderveen original https://aws.amazon.com/blogs/security/how-to-patch-linux-workloads-on-aws/

Most malware tries to compromise your systems by using a known vulnerability that the operating system maker has already patched. As best practices to help prevent malware from affecting your systems, you should apply all operating system patches and actively monitor your systems for missing patches.

In this blog post, I show you how to patch Linux workloads using AWS Systems Manager. To accomplish this, I will show you how to use the AWS Command Line Interface (AWS CLI) to:

  1. Launch an Amazon EC2 instance for use with Systems Manager.
  2. Configure Systems Manager to patch your Amazon EC2 Linux instances.

In two previous blog posts (Part 1 and Part 2), I showed how to use the AWS Management Console to perform the necessary steps to patch, inspect, and protect Microsoft Windows workloads. You can implement those same processes for your Linux instances running in AWS by changing the instance tags and types shown in the previous blog posts.

Because most Linux system administrators are more familiar with using a command line, I show how to patch Linux workloads by using the AWS CLI in this blog post. The steps to use the Amazon EBS Snapshot Scheduler and Amazon Inspector are identical for both Microsoft Windows and Linux.

What you should know first

To follow along with the solution in this post, you need one or more Amazon EC2 instances. You may use existing instances or create new instances. For this post, I assume this is an Amazon EC2 for Amazon Linux instance installed from Amazon Machine Images (AMIs).

Systems Manager is a collection of capabilities that helps you automate management tasks for AWS-hosted instances on Amazon EC2 and your on-premises servers. In this post, I use Systems Manager for two purposes: to run remote commands and apply operating system patches. To learn about the full capabilities of Systems Manager, see What Is AWS Systems Manager?

As of Amazon Linux 2017.09, the AMI comes preinstalled with the Systems Manager agent. Systems Manager Patch Manager also supports Red Hat and Ubuntu. To install the agent on these Linux distributions or an older version of Amazon Linux, see Installing and Configuring SSM Agent on Linux Instances.

If you are not familiar with how to launch an Amazon EC2 instance, see Launching an Instance. I also assume you launched or will launch your instance in a private subnet. You must make sure that the Amazon EC2 instance can connect to the internet using a network address translation (NAT) instance or NAT gateway to communicate with Systems Manager. The following diagram shows how you should structure your VPC.

Diagram showing how to structure your VPC

Later in this post, you will assign tasks to a maintenance window to patch your instances with Systems Manager. To do this, the IAM user you are using for this post must have the iam:PassRole permission. This permission allows the IAM user assigning tasks to pass his own IAM permissions to the AWS service. In this example, when you assign a task to a maintenance window, IAM passes your credentials to Systems Manager. You also should authorize your IAM user to use Amazon EC2 and Systems Manager. As mentioned before, you will be using the AWS CLI for most of the steps in this blog post. Our documentation shows you how to get started with the AWS CLI. Make sure you have the AWS CLI installed and configured with an AWS access key and secret access key that belong to an IAM user that have the following AWS managed policies attached to the IAM user you are using for this example: AmazonEC2FullAccess and AmazonSSMFullAccess.

Step 1: Launch an Amazon EC2 Linux instance

In this section, I show you how to launch an Amazon EC2 instance so that you can use Systems Manager with the instance. This step requires you to do three things:

  1. Create an IAM role for Systems Manager before launching your Amazon EC2 instance.
  2. Launch your Amazon EC2 instance with Amazon EBS and the IAM role for Systems Manager.
  3. Add tags to the instances so that you can add your instances to a Systems Manager maintenance window based on tags.

A. Create an IAM role for Systems Manager

Before launching an Amazon EC2 instance, I recommend that you first create an IAM role for Systems Manager, which you will use to update the Amazon EC2 instance. AWS already provides a preconfigured policy that you can use for the new role and it is called AmazonEC2RoleforSSM.

  1. Create a JSON file named trustpolicy-ec2ssm.json that contains the following trust policy. This policy describes which principal (an entity that can take action on an AWS resource) is allowed to assume the role we are going to create. In this example, the principal is the Amazon EC2 service.
      "Version": "2012-10-17",
      "Statement": {
        "Effect": "Allow",
        "Principal": {"Service": "ec2.amazonaws.com"},
        "Action": "sts:AssumeRole"

  1. Use the following command to create a role named EC2SSM that has the AWS managed policy AmazonEC2RoleforSSM attached to it. This generates JSON-based output that describes the role and its parameters, if the command is successful.
    $ aws iam create-role --role-name EC2SSM --assume-role-policy-document file://trustpolicy-ec2ssm.json

  1. Use the following command to attach the AWS managed IAM policy (AmazonEC2RoleforSSM) to your newly created role.
    $ aws iam attach-role-policy --role-name EC2SSM --policy-arn arn:aws:iam::aws:policy/service-role/AmazonEC2RoleforSSM

  1. Use the following commands to create the IAM instance profile and add the role to the instance profile. The instance profile is needed to attach the role we created earlier to your Amazon EC2 instance.
    $ aws iam create-instance-profile --instance-profile-name EC2SSM-IP
    $ aws iam add-role-to-instance-profile --instance-profile-name EC2SSM-IP --role-name EC2SSM

B. Launch your Amazon EC2 instance

To follow along, you need an Amazon EC2 instance that is running Amazon Linux. You can use any existing instance you may have or create a new instance.

When launching a new Amazon EC2 instance, be sure that:

  1. Use the following command to launch a new Amazon EC2 instance using an Amazon Linux AMI available in the US East (N. Virginia) Region (also known as us-east-1). Replace YourKeyPair and YourSubnetId with your information. For more information about creating a key pair, see the create-key-pair documentation. Write down the InstanceId that is in the output because you will need it later in this post.
    $ aws ec2 run-instances --image-id ami-cb9ec1b1 --instance-type t2.micro --key-name YourKeyPair --subnet-id YourSubnetId --iam-instance-profile Name=EC2SSM-IP

  1. If you are using an existing Amazon EC2 instance, you can use the following command to attach the instance profile you created earlier to your instance.
    $ aws ec2 associate-iam-instance-profile --instance-id YourInstanceId --iam-instance-profile Name=EC2SSM-IP

C. Add tags

The final step of configuring your Amazon EC2 instances is to add tags. You will use these tags to configure Systems Manager in Step 2 of this post. For this example, I add a tag named Patch Group and set the value to Linux Servers. I could have other groups of Amazon EC2 instances that I treat differently by having the same tag name but a different tag value. For example, I might have a collection of other servers with the tag name Patch Group with a value of Web Servers.

  • Use the following command to add the Patch Group tag to your Amazon EC2 instance.
    $ aws ec2 create-tags --resources YourInstanceId --tags --tags Key="Patch Group",Value="Linux Servers"

Note: You must wait a few minutes until the Amazon EC2 instance is available before you can proceed to the next section. To make sure your Amazon EC2 instance is online and ready, you can use the following AWS CLI command:

$ aws ec2 describe-instance-status --instance-ids YourInstanceId

At this point, you now have at least one Amazon EC2 instance you can use to configure Systems Manager.

Step 2: Configure Systems Manager

In this section, I show you how to configure and use Systems Manager to apply operating system patches to your Amazon EC2 instances, and how to manage patch compliance.

To start, I provide some background information about Systems Manager. Then, I cover how to:

  1. Create the Systems Manager IAM role so that Systems Manager is able to perform patch operations.
  2. Create a Systems Manager patch baseline and associate it with your instance to define which patches Systems Manager should apply.
  3. Define a maintenance window to make sure Systems Manager patches your instance when you tell it to.
  4. Monitor patch compliance to verify the patch state of your instances.

You must meet two prerequisites to use Systems Manager to apply operating system patches. First, you must attach the IAM role you created in the previous section, EC2SSM, to your Amazon EC2 instance. Second, you must install the Systems Manager agent on your Amazon EC2 instance. If you have used a recent Amazon Linux AMI, Amazon has already installed the Systems Manager agent on your Amazon EC2 instance. You can confirm this by logging in to an Amazon EC2 instance and checking the Systems Manager agent log files that are located at /var/log/amazon/ssm/.

To install the Systems Manager agent on an instance that does not have the agent preinstalled or if you want to use the Systems Manager agent on your on-premises servers, see Installing and Configuring the Systems Manager Agent on Linux Instances. If you forgot to attach the newly created role when launching your Amazon EC2 instance or if you want to attach the role to already running Amazon EC2 instances, see Attach an AWS IAM Role to an Existing Amazon EC2 Instance by Using the AWS CLI or use the AWS Management Console.

A. Create the Systems Manager IAM role

For a maintenance window to be able to run any tasks, you must create a new role for Systems Manager. This role is a different kind of role than the one you created earlier: this role will be used by Systems Manager instead of Amazon EC2. Earlier, you created the role, EC2SSM, with the policy, AmazonEC2RoleforSSM, which allowed the Systems Manager agent on your instance to communicate with Systems Manager. In this section, you need a new role with the policy, AmazonSSMMaintenanceWindowRole, so that the Systems Manager service can execute commands on your instance.

To create the new IAM role for Systems Manager:

  1. Create a JSON file named trustpolicy-maintenancewindowrole.json that contains the following trust policy. This policy describes which principal is allowed to assume the role you are going to create. This trust policy allows not only Amazon EC2 to assume this role, but also Systems Manager.

  1. Use the following command to create a role named MaintenanceWindowRole that has the AWS managed policy, AmazonSSMMaintenanceWindowRole, attached to it. This command generates JSON-based output that describes the role and its parameters, if the command is successful.
    $ aws iam create-role --role-name MaintenanceWindowRole --assume-role-policy-document file://trustpolicy-maintenancewindowrole.json

  1. Use the following command to attach the AWS managed IAM policy (AmazonEC2RoleforSSM) to your newly created role.
    $ aws iam attach-role-policy --role-name MaintenanceWindowRole --policy-arn arn:aws:iam::aws:policy/service-role/AmazonSSMMaintenanceWindowRole

B. Create a Systems Manager patch baseline and associate it with your instance

Next, you will create a Systems Manager patch baseline and associate it with your Amazon EC2 instance. A patch baseline defines which patches Systems Manager should apply to your instance. Before you can associate the patch baseline with your instance, though, you must determine if Systems Manager recognizes your Amazon EC2 instance. Use the following command to list all instances managed by Systems Manager. The --filters option ensures you look only for your newly created Amazon EC2 instance.

$ aws ssm describe-instance-information --filters Key=InstanceIds,Values= YourInstanceId

    "InstanceInformationList": [
            "IsLatestVersion": true,
            "ComputerName": "ip-10-50-2-245",
            "PingStatus": "Online",
            "InstanceId": "YourInstanceId",
            "IPAddress": "",
            "ResourceType": "EC2Instance",
            "AgentVersion": "",
            "PlatformVersion": "2017.09",
            "PlatformName": "Amazon Linux AMI",
            "PlatformType": "Linux",
            "LastPingDateTime": 1515759143.826

If your instance is missing from the list, verify that:

  1. Your instance is running.
  2. You attached the Systems Manager IAM role, EC2SSM.
  3. You deployed a NAT gateway in your public subnet to ensure your VPC reflects the diagram shown earlier in this post so that the Systems Manager agent can connect to the Systems Manager internet endpoint.
  4. The Systems Manager agent logs don’t include any unaddressed errors.

Now that you have checked that Systems Manager can manage your Amazon EC2 instance, it is time to create a patch baseline. With a patch baseline, you define which patches are approved to be installed on all Amazon EC2 instances associated with the patch baseline. The Patch Group resource tag you defined earlier will determine to which patch group an instance belongs. If you do not specifically define a patch baseline, the default AWS-managed patch baseline is used.

To create a patch baseline:

  1. Use the following command to create a patch baseline named AmazonLinuxServers. With approval rules, you can determine the approved patches that will be included in your patch baseline. In this example, you add all Critical severity patches to the patch baseline as soon as they are released, by setting the Auto approval delay to 0 days. By setting the Auto approval delay to 2 days, you add to this patch baseline the Important, Medium, and Low severity patches two days after they are released.
    $ aws ssm create-patch-baseline --name "AmazonLinuxServers" --description "Baseline containing all updates for Amazon Linux" --operating-system AMAZON_LINUX --approval-rules "PatchRules=[{PatchFilterGroup={PatchFilters=[{Values=[Critical],Key=SEVERITY}]},ApproveAfterDays=0,ComplianceLevel=CRITICAL},{PatchFilterGroup={PatchFilters=[{Values=[Important,Medium,Low],Key=SEVERITY}]},ApproveAfterDays=2,ComplianceLevel=HIGH}]"
        "BaselineId": "YourBaselineId"

  1. Use the following command to register the patch baseline you created with your instance. To do so, you use the Patch Group tag that you added to your Amazon EC2 instance.
    $ aws ssm register-patch-baseline-for-patch-group --baseline-id YourPatchBaselineId --patch-group "Linux Servers"
        "PatchGroup": "Linux Servers",
        "BaselineId": "YourBaselineId"

C.  Define a maintenance window

Now that you have successfully set up a role, created a patch baseline, and registered your Amazon EC2 instance with your patch baseline, you will define a maintenance window so that you can control when your Amazon EC2 instances will receive patches. By creating multiple maintenance windows and assigning them to different patch groups, you can make sure your Amazon EC2 instances do not all reboot at the same time.

To define a maintenance window:

  1. Use the following command to define a maintenance window. In this example command, the maintenance window will start every Saturday at 10:00 P.M. UTC. It will have a duration of 4 hours and will not start any new tasks 1 hour before the end of the maintenance window.
    $ aws ssm create-maintenance-window --name SaturdayNight --schedule "cron(0 0 22 ? * SAT *)" --duration 4 --cutoff 1 --allow-unassociated-targets
        "WindowId": "YourMaintenanceWindowId"

For more information about defining a cron-based schedule for maintenance windows, see Cron and Rate Expressions for Maintenance Windows.

  1. After defining the maintenance window, you must register the Amazon EC2 instance with the maintenance window so that Systems Manager knows which Amazon EC2 instance it should patch in this maintenance window. You can register the instance by using the same Patch Group tag you used to associate the Amazon EC2 instance with the AWS-provided patch baseline, as shown in the following command.
    $ aws ssm register-target-with-maintenance-window --window-id YourMaintenanceWindowId --resource-type INSTANCE --targets "Key=tag:Patch Group,Values=Linux Servers"
        "WindowTargetId": "YourWindowTargetId"

  1. Assign a task to the maintenance window that will install the operating system patches on your Amazon EC2 instance. The following command includes the following options.
    1. name is the name of your task and is optional. I named mine Patching.
    2. task-arn is the name of the task document you want to run.
    3. max-concurrency allows you to specify how many of your Amazon EC2 instances Systems Manager should patch at the same time. max-errors determines when Systems Manager should abort the task. For patching, this number should not be too low, because you do not want your entire patch task to stop on all instances if one instance fails. You can set this, for example, to 20%.
    4. service-role-arn is the Amazon Resource Name (ARN) of the AmazonSSMMaintenanceWindowRole role you created earlier in this blog post.
    5. task-invocation-parameters defines the parameters that are specific to the AWS-RunPatchBaseline task document and tells Systems Manager that you want to install patches with a timeout of 600 seconds (10 minutes).
      $ aws ssm register-task-with-maintenance-window --name "Patching" --window-id "YourMaintenanceWindowId" --targets "Key=WindowTargetIds,Values=YourWindowTargetId" --task-arn AWS-RunPatchBaseline --service-role-arn "arn:aws:iam::123456789012:role/MaintenanceWindowRole" --task-type "RUN_COMMAND" --task-invocation-parameters "RunCommand={Comment=,TimeoutSeconds=600,Parameters={SnapshotId=[''],Operation=[Install]}}" --max-concurrency "500" --max-errors "20%"
          "WindowTaskId": "YourWindowTaskId"

Now, you must wait for the maintenance window to run at least once according to the schedule you defined earlier. If your maintenance window has expired, you can check the status of any maintenance tasks Systems Manager has performed by using the following command.

$ aws ssm describe-maintenance-window-executions --window-id "YourMaintenanceWindowId"

    "WindowExecutions": [
            "Status": "SUCCESS",
            "WindowId": "YourMaintenanceWindowId",
            "WindowExecutionId": "b594984b-430e-4ffa-a44c-a2e171de9dd3",
            "EndTime": 1515766467.487,
            "StartTime": 1515766457.691

D.  Monitor patch compliance

You also can see the overall patch compliance of all Amazon EC2 instances using the following command in the AWS CLI.

$ aws ssm list-compliance-summaries

This command shows you the number of instances that are compliant with each category and the number of instances that are not in JSON format.

You also can see overall patch compliance by choosing Compliance under Insights in the navigation pane of the Systems Manager console. You will see a visual representation of how many Amazon EC2 instances are up to date, how many Amazon EC2 instances are noncompliant, and how many Amazon EC2 instances are compliant in relation to the earlier defined patch baseline.

Screenshot of the Compliance page of the Systems Manager console

In this section, you have set everything up for patch management on your instance. Now you know how to patch your Amazon EC2 instance in a controlled manner and how to check if your Amazon EC2 instance is compliant with the patch baseline you have defined. Of course, I recommend that you apply these steps to all Amazon EC2 instances you manage.


In this blog post, I showed how to use Systems Manager to create a patch baseline and maintenance window to keep your Amazon EC2 Linux instances up to date with the latest security patches. Remember that by creating multiple maintenance windows and assigning them to different patch groups, you can make sure your Amazon EC2 instances do not all reboot at the same time.

If you have comments about this post, submit them in the “Comments” section below. If you have questions about or issues implementing any part of this solution, start a new thread on the Amazon EC2 forum or contact AWS Support.

– Koen

Troubleshooting event publishing issues in Amazon SES

Post Syndicated from Dustin Taylor original https://aws.amazon.com/blogs/ses/troubleshooting-event-publishing-issues-in-amazon-ses/

Over the past year, we’ve released several features that make it easier to track the metrics that are associated with your Amazon SES account. The first of these features, launched in November of last year, was event publishing.

Initially, event publishing let you capture basic metrics related to your email sending and publish them to other AWS services, such as Amazon CloudWatch and Amazon Kinesis Data Firehose. Some examples of these basic metrics include the number of emails that were sent and delivered, as well as the number that bounced or received complaints. A few months ago, we expanded this feature by adding engagement metrics—specifically, information about the number of emails that your customers opened or engaged with by clicking links.

As a former Cloud Support Engineer, I’ve seen Amazon SES customers do some amazing things with event publishing, but I’ve also seen some common issues. In this article, we look at some of these issues, and discuss the steps you can take to resolve them.

Before we begin

This post assumes that your Amazon SES account is already out of the sandbox, that you’ve verified an identity (such as an email address or domain), and that you have the necessary permissions to use Amazon SES and the service that you’ll publish event data to (such as Amazon SNS, CloudWatch, or Kinesis Data Firehose).

We also assume that you’re familiar with the process of creating configuration sets and specifying event destinations for those configuration sets. For more information, see Using Amazon SES Configuration Sets in the Amazon SES Developer Guide.

Amazon SNS event destinations

If you want to receive notifications when events occur—such as when recipients click a link in an email, or when they report an email as spam—you can use Amazon SNS as an event destination.

Occasionally, customers ask us why they’re not receiving notifications when they use an Amazon SNS topic as an event destination. One of the most common reasons for this issue is that they haven’t configured subscriptions for their Amazon SNS topic yet.

A single topic in Amazon SNS can have one or more subscriptions. When you subscribe to a topic, you tell that topic which endpoints (such as email addresses or mobile phone numbers) to contact when it receives a notification. If you haven’t set up any subscriptions, nothing will happen when an email event occurs.

For more information about setting up topics and subscriptions, see Getting Started in the Amazon SNS Developer Guide. For information about publishing Amazon SES events to Amazon SNS topics, see Set Up an Amazon SNS Event Destination for Amazon SES Event Publishing in the Amazon SES Developer Guide.

Kinesis Data Firehose event destinations

If you want to store your Amazon SES event data for the long term, choose Amazon Kinesis Data Firehose as a destination for Amazon SES events. With Kinesis Data Firehose, you can stream data to Amazon S3 or Amazon Redshift for storage and analysis.

The process of setting up Kinesis Data Firehose as an event destination is similar to the process for setting up Amazon SNS: you choose the types of events (such as deliveries, opens, clicks, or bounces) that you want to export, and the name of the Kinesis Data Firehose stream that you want to export to. However, there’s one important difference. When you set up a Kinesis Data Firehose event destination, you must also choose the IAM role that Amazon SES uses to send event data to Kinesis Data Firehose.

When you set up the Kinesis Data Firehose event destination, you can choose to have Amazon SES create the IAM role for you automatically. For many users, this is the best solution—it ensures that the IAM role has the appropriate permissions to move event data from Amazon SES to Kinesis Data Firehose.

Customers occasionally run into issues with the Kinesis Data Firehose event destination when they use an existing IAM role. If you use an existing IAM role, or create a new role for this purpose, make sure that the role includes the firehose:PutRecord and firehose:PutRecordBatch permissions. If the role doesn’t include these permissions, then the Amazon SES event data isn’t published to Kinesis Data Firehose. For more information, see Controlling Access with Amazon Kinesis Data Firehose in the Amazon Kinesis Data Firehose Developer Guide.

CloudWatch event destinations

By publishing your Amazon SES event data to Amazon CloudWatch, you can create dashboards that track your sending statistics in real time, as well as alarms that notify you when your event metrics reach certain thresholds.

The amount that you’re charged for using CloudWatch is based on several factors, including the number of metrics you use. In order to give you more control over the specific metrics you send to CloudWatch—and to help you avoid unexpected charges—you can limit the email sending events that are sent to CloudWatch.

When you choose CloudWatch as an event destination, you must choose a value source. The value source can be one of three options: a message tag, a link tag, or an email header. After you choose a value source, you then specify a name and a value. When you send an email using a configuration set that refers to a CloudWatch event destination, it only sends the metrics for that email to CloudWatch if the email contains the name and value that you specified as the value source. This requirement is commonly overlooked.

For example, assume that you chose Message Tag as the value source, and specified “CategoryId” as the dimension name and “31415” as the dimension value. When you want to send events for an email to CloudWatch, you must specify the name of the configuration set that uses the CloudWatch destination. You must also include a tag in your message. The name of the tag must be “CategoryId” and the value must be “31415”.

For more information about adding tags and email headers to your messages, see Send Email Using Amazon SES Event Publishing in the Amazon SES Developer Guide. For more information about adding tags to links, see Amazon SES Email Sending Metrics FAQs in the Amazon SES Developer Guide.

Troubleshooting event publishing for open and click data

Occasionally, customers ask why they’re not seeing open and click data for their emails. This issue most often occurs when the customer only sends text versions of their emails. Because of the way Amazon SES tracks open and click events, you can only see open and click data for emails that are sent as HTML. For more information about how Amazon SES modifies your emails when you enable open and click tracking, see Amazon SES Email Sending Metrics FAQs in the Amazon SES Developer Guide.

The process that you use to send HTML emails varies based on the email sending method you use. The Code Examples section of the Amazon SES Developer Guide contains examples of several methods of sending email by using the Amazon SES SMTP interface or an AWS SDK. All of the examples in this section include methods for sending HTML (as well as text-only) emails.

If you encounter any issues that weren’t covered in this post, please open a case in the Support Center and we’d be more than happy to assist.

Give Your WordPress Blog a Voice With Our New Amazon Polly Plugin

Post Syndicated from Jeff Barr original https://aws.amazon.com/blogs/aws/give-your-wordpress-blog-a-voice-with-our-new-amazon-polly-plugin/

I first told you about Polly in late 2016 in my post Amazon Polly – Text to Speech in 47 Voices and 24 Languages. After that AWS re:Invent launch, we added support for Korean, five new voices, and made Polly available in all Regions in the aws partition. We also added whispering, speech marks, a timbre effect, and dynamic range compression.

New WordPress Plugin
Today we are launching a WordPress plugin that uses Polly to create high-quality audio versions of your blog posts. You can access the audio from within the post or in podcast form using a feature that we call Amazon Pollycast! Both options make your content more accessible and can help you to reach a wider audience. This plugin was a joint effort between the AWS team our friends at AWS Advanced Technology Partner WP Engine.

As you will see, the plugin is easy to install and configure. You can use it with installations of WordPress that you run on your own infrastructure or on AWS. Either way, you have access to all of Polly’s voices along with a wide variety of configuration options. The generated audio (an MP3 file for each post) can be stored alongside your WordPress content, or in Amazon Simple Storage Service (S3), with optional support for content distribution via Amazon CloudFront.

Installing the Plugin
I did not have an existing WordPress-powered blog, so I begin by launching a Lightsail instance using the WordPress 4.8.1 blueprint:

Then I follow these directions to access my login credentials:

Credentials in hand, I log in to the WordPress Dashboard:

The plugin makes calls to AWS, and needs to have credentials in order to do so. I hop over to the IAM Console and created a new policy. The policy allows the plugin to access a carefully selected set of S3 and Polly functions (find the full policy in the README):

Then I create an IAM user (wp-polly-user). I enter the name and indicate that it will be used for Programmatic Access:

Then I attach the policy that I just created, and click on Review:

I review my settings (not shown) and then click on Create User. Then I copy the two values (Access Key ID and Secret Access Key) into a secure location. Possession of these keys allows the bearer to make calls to AWS so I take care not to leave them lying around.

Now I am ready to install the plugin! I go back to the WordPress Dashboard and click on Add New in the Plugins menu:

Then I click on Upload Plugin and locate the ZIP file that I downloaded from the WordPress Plugins site. After I find it I click on Install Now to proceed:

WordPress uploads and installs the plugin. Now I click on Activate Plugin to move ahead:

With the plugin installed, I click on Settings to set it up:

I enter my keys and click on Save Changes:

The General settings let me control the sample rate, voice, player position, the default setting for new posts, and the autoplay option. I can leave all of the settings as-is to get started:

The Cloud Storage settings let me store audio in S3 and to use CloudFront to distribute the audio:

The Amazon Pollycast settings give me control over the iTunes parameters that are included in the generated RSS feed:

Finally, the Bulk Update button lets me regenerate all of the audio files after I change any of the other settings:

With the plugin installed and configured, I can create a new post. As you can see, the plugin can be enabled and customized for each post:

I can see how much it will cost to convert to audio with a click:

When I click on Publish, the plugin breaks the text into multiple blocks on sentence boundaries, calls the Polly SynthesizeSpeech API for each block, and accumulates the resulting audio in a single MP3 file. The published blog post references the file using the <audio> tag. Here’s the post:

I can’t seem to use an <audio> tag in this post, but you can download and play the MP3 file yourself if you’d like.

The Pollycast feature generates an RSS file with links to an MP3 file for each post:

The plugin will make calls to Amazon Polly each time the post is saved or updated. Pricing is based on the number of characters in the speech requests, as described on the Polly Pricing page. Also, the AWS Free Tier lets you process up to 5 million characters per month at no charge, for a period of one year that starts when you make your first call to Polly.

Going Further
The plugin is available on GitHub in source code form and we are looking forward to your pull requests! Here are a couple of ideas to get you started:

Voice Per Author – Allow selection of a distinct Polly voice for each author.

Quoted Text – For blogs that make frequent use of embedded quotes, use a distinct voice for the quotes.

Translation – Use Amazon Translate to translate the texts into another language, and then use Polly to generate audio in that language.

Other Blogging Engines – Build a similar plugin for your favorite blogging engine.

SSML Support – Figure out an interesting way to use Polly’s SSML tags to add additional character to the audio.

Let me know what you come up with!



Recent EC2 Goodies – Launch Templates and Spread Placement

Post Syndicated from Jeff Barr original https://aws.amazon.com/blogs/aws/recent-ec2-goodies-launch-templates-and-spread-placement/

We launched some important new EC2 instance types and features at AWS re:Invent. I’ve already told you about the M5, H1, T2 Unlimited and Bare Metal instances, and about Spot features such as Hibernation and the New Pricing Model. Randall told you about the Amazon Time Sync Service. Today I would like to tell you about two of the features that we launched: Spread placement groups and Launch Templates. Both features are available in the EC2 Console and from the EC2 APIs, and can be used in all of the AWS Regions in the “aws” partition:

Launch Templates
You can use launch templates to store the instance, network, security, storage, and advanced parameters that you use to launch EC2 instances, and can also include any desired tags. Each template can include any desired subset of the full collection of parameters. You can, for example, define common configuration parameters such as tags or network configurations in a template, and allow the other parameters to be specified as part of the actual launch.

Templates give you the power to set up a consistent launch environment that spans instances launched in On-Demand and Spot form, as well as through EC2 Auto Scaling and as part of a Spot Fleet. You can use them to implement organization-wide standards and to enforce best practices, and you can give your IAM users the ability to launch instances via templates while withholding the ability to do so via the underlying APIs.

Templates are versioned and you can use any desired version when you launch an instance. You can create templates from scratch, base them on the previous version, or copy the parameters from a running instance.

Here’s how you create a launch template in the Console:

Here’s how to include network interfaces, storage volumes, tags, and security groups:

And here’s how to specify advanced and specialized parameters:

You don’t have to specify values for all of these parameters in your templates; enter the values that are common to multiple instances or launches and specify the rest at launch time.

When you click Create launch template, the template is created and can be used to launch On-Demand instances, create Auto Scaling Groups, and create Spot Fleets:

The Launch Instance button now gives you the option to launch from a template:

Simply choose the template and the version, and finalize all of the launch parameters:

You can also manage your templates and template versions from the Console:

To learn more about this feature, read Launching an Instance from a Launch Template.

Spread Placement Groups
Spread placement groups indicate that you do not want the instances in the group to share the same underlying hardware. Applications that rely on a small number of critical instances can launch them in a spread placement group to reduce the odds that one hardware failure will impact more than one instance. Here are a couple of things to keep in mind when you use spread placement groups:

  • Availability Zones – A single spread placement group can span multiple Availability Zones. You can have a maximum of seven running instances per Availability Zone per group.
  • Unique Hardware – Launch requests can fail if there is insufficient unique hardware available. The situation changes over time as overall usage changes and as we add additional hardware; you can retry failed requests at a later time.
  • Instance Types – You can launch a wide variety of M4, M5, C3, R3, R4, X1, X1e, D2, H1, I2, I3, HS1, F1, G2, G3, P2, and P3 instances types in spread placement groups.
  • Reserved Instances – Instances launched into a spread placement group can make use of reserved capacity. However, you cannot currently reserve capacity for a placement group and could receive an ICE (Insufficient Capacity Error) even if you have some RI’s available.
  • Applicability – You cannot use spread placement groups in conjunction with Dedicated Instances or Dedicated Hosts.

You can create and use spread placement groups from the AWS Management Console, the AWS Command Line Interface (CLI), the AWS Tools for Windows PowerShell, and the AWS SDKs. The console has a new feature that will help you to learn how to use the command line:

You can specify an existing placement group or create a new one when you launch an EC2 instance:

To learn more, read about Placement Groups.