Tag Archives: appstream 2.0

How to record a video of Amazon AppStream 2.0 streaming sessions

Post Syndicated from Nicolas Malaval original https://aws.amazon.com/blogs/security/how-to-record-video-of-amazon-appstream-2-0-streaming-sessions/

Amazon AppStream 2.0 is a fully managed service that lets you stream applications and desktops to your users. In this post, I’ll show you how to record a video of AppStream 2.0 streaming sessions by using FFmpeg, a popular media framework.

There are many use cases for session recording, such as auditing administrative access, troubleshooting user issues, or quality assurance. For example, you could publish administrative tools with AppStream 2.0, such as a Remote Desktop Protocol (RDP) client, to protect access to your backend systems (see How to use Amazon AppStream 2.0 to reduce your bastion host attack surface) and you may want to record a video of what your administrators do when accessing and operating backend systems. You may also want to see what a user did to reproduce an issue, or view activities in a call center setting, such as call handling or customer support, for review and training.

This solution is not designed or intended for people surveillance, or for the collection of evidence for legal proceedings. You are responsible for complying with all applicable laws and regulations when using this solution.

Overview and architecture

In this section, you can learn about the steps for recording AppStream 2.0 streaming sessions and see an overview of the solution architecture. Later in this post, you can find instructions about how to implement and test the solution.

AppStream 2.0 enables you to run custom scripts to prepare the streaming instance before the applications launch or after the streaming session has completed. Figure 1 shows a simplified description of what happens before, during and after a streaming session.
 

Figure 1: Solution architecture

Figure 1: Solution architecture

  1. Before the streaming session starts, AppStream 2.0 runs script A, which uses PsExec, a utility that enables administrators to run commands on local or remote computers, to launch script B. Script B then runs during the entire streaming session. PsExec can run the script as the LocalSystem account, a service account that has extensive privileges on a local system, while it interacts with the desktop of another session. Using the LocalSystem account, you can use FFmpeg to record the session screen and prevent AppStream 2.0 users from stopping or tampering with the solution, as long as they aren’t granted local administrator rights.
  2. Script B launches FFmpeg and starts recording the desktop. The solution uses the FFmpeg built-in screen-grabber to capture the desktop across all the available screens.
  3. When FFmpeg starts recording, it captures the area covered by the desktop at that time. If the number of screens or the resolution changes, a portion of the desktop might be outside the recorded area. In that case, script B stops the recording and starts FFmpeg again.
  4. After the streaming session ends, AppStream 2.0 runs script C, which notifies script B that it must end the recording and close. Script B stops FFmpeg.
  5. Before exiting, script B uploads the video files that FFmpeg generated to Amazon Simple Storage Service (Amazon S3). It also stores user and session metadata in Amazon S3, along with the video files, for easy retrieval of session recordings.

For a more comprehensive understanding of how the session scripts works, you can refer to the GitHub repository that contains the solution artifacts, where I go into the details of each script.

Implementing and testing the solution

Now that you understand the architecture of this solution, you can follow the instructions in this section to implement this blog post’s solution in your AWS account. You will:

  1. Create a virtual private cloud (VPC), an S3 bucket and an AWS Identity and Access Management (IAM) role with AWS CloudFormation.
  2. Create an AppStream 2.0 image builder.
  3. Configure the solution scripts on the image builder.
  4. Specify an application to publish and create an image.
  5. Create an AppStream 2.0 fleet.
  6. Create an AppStream 2.0 stack.
  7. Create a user in the AppStream 2.0 user pool.
  8. Launch a streaming session and test the solution.

Step 1: Create a VPC, an S3 bucket, and an IAM role with AWS CloudFormation

For the first step in the solution, you create a new VPC where AppStream 2.0 will be deployed, or choose an existing VPC, a new S3 bucket to store the session recordings, and a new IAM role to grant AppStream 2.0 the necessary IAM permissions.

To create the VPC, the S3 bucket, and the IAM role with AWS CloudFormation

  1. Select the following Launch Stack button to open the CloudFormation console and create a CloudFormation stack from the template. You can change the Region where resources are deployed in the navigation bar.
     
    Select the Launch Stack button to launch the template

    The latest template can also be downloaded on GitHub.

  2. Choose Next. For VPC ID, Subnet 1 ID and Subnet 2 ID, you can optionally select a VPC and two subnets, if you want to deploy the solution in an existing VPC, or leave these fields blank to create a new VPC. Then follow the on-screen instructions. AWS CloudFormation creates the following resources:
    • (If you chose to create a new VPC) An Amazon Virtual Private Cloud (Amazon VPC) with an internet gateway attached.
    • (If you chose to create a new VPC) Two public subnets on this Amazon VPC with a new route table to make them publicly accessible.
    • An S3 bucket to store the session recordings.
    • An IAM role to grant AppStream 2.0 permissions to upload video and metadata files to Amazon S3.
  3. After the stack creation has completed, choose the Outputs tab in the CloudFormation console and note the values that the process returned: the name and Region of the S3 bucket, the name of the IAM role, the ID of the VPC, and the two subnets.

Step 2: Create an AppStream 2.0 image builder

The next step is to create a new AppStream 2.0 image builder. An image builder is a virtual machine that you can use to install and configure applications for streaming, and then create a custom image.

To create the AppStream 2.0 image builder

  1. Open the AppStream 2.0 console and select the Region in the navigation bar. Choose Get Started then Skip if you are new to the console.
  2. Choose Images in the left pane, and then choose Image Builder. Choose Launch Image Builder.
  3. In Step 1: Choose Image:
    1. Select the name of the latest AppStream 2.0 base image for the Windows Server version of your choice. You can find its name in the AppStream 2.0 base image version history. For example, at the time of writing, the name of the latest Windows Server 2019 base image is AppStream-WinServer2019-07-16-2020.
    2. Choose Next.
  4. In Step 2: Configure Image Builder:
    1. For Name, enter session-recording.
    2. For Instance Type, choose stream.standard.medium.
    3. For IAM role, select the IAM role that AWS CloudFormation created.
    4. Choose Next.
  5. In Step 3: Configure Network:
    1. Choose Default Internet Access to provide internet access to your image builder.
    2. For VPC, select the ID of the VPC, and for Subnet 1, select the ID of Subnet 1.
    3. For Security group(s), select the ID of the security group. Refer back to the Outputs tab of the CloudFormation stack if you are unsure which VPC, subnet and security group to select.
    4. Choose Review.
  6. In Step 4: Review, choose Launch.

Step 3: Configure the solution scripts on the image builder

The session scripts to run before streaming sessions start or after sessions end are specified within an AppStream 2.0 image. In this step, you install the solution scripts on your image builder and specify the scripts to run in the session scripts configuration file.

To configure the solution scripts on the image builder

  1. Wait until the image builder is in the Running state, and then choose Connect.
  2. Within the AppStream 2.0 streaming session, on the Local User tab, choose Administrator.
  3. To install the solution scripts:
    1. From the image builder desktop, choose Start in the Windows taskbar.
    2. Open the context (right-click) menu for Windows PowerShell, and then choose Run as Administrator.
    3. Run the following commands in the PowerShell terminal to create the required folders, and to copy the solution scripts and the session scripts configuration file from public objects in GitHub to the local disk. If you aren’t using Google Chrome or the AppStream 2.0 client, you need to choose the Clipboard icon in the AppStream 2.0 navigation bar, and then select Paste to remote session.
      New-Item -Path C:\SessionRecording -ItemType directory
      New-Item -Path C:\SessionRecording\Scripts -ItemType directory
      New-Item -Path C:\SessionRecording\Output -ItemType directory
      New-Item -Path C:\SessionRecording\Bin -ItemType directory
      
      $Acl = Get-Acl C:\SessionRecording
      $Acl.SetAccessRuleProtection($true,$false)
      $AccessRule1 = New-Object System.Security.AccessControl.FileSystemAccessRule("Administrators","FullControl","ContainerInherit,ObjectInherit","None","Allow")
      $Acl.SetAccessRule($AccessRule1)
      $AccessRule2 = New-Object System.Security.AccessControl.FileSystemAccessRule("SYSTEM","FullControl","ContainerInherit,ObjectInherit","None","Allow")
      $Acl.SetAccessRule($AccessRule2)
      $AccessRule3 = New-Object System.Security.AccessControl.FileSystemAccessRule("ImageBuilderAdmin","FullControl","ContainerInherit,ObjectInherit","None","Allow")
      $Acl.SetAccessRule($AccessRule3)
      Set-Acl C:\SessionRecording $Acl
      
      [Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12
      Invoke-WebRequest -URI https://github.com/aws-samples/appstream-session-recording/raw/main/script_a.ps1 -OutFile C:\SessionRecording\Scripts\script_a.ps1
      Invoke-WebRequest -URI https://github.com/aws-samples/appstream-session-recording/raw/main/script_b.ps1 -OutFile C:\SessionRecording\Scripts\script_b.ps1
      Invoke-WebRequest -URI https://github.com/aws-samples/appstream-session-recording/raw/main/script_c.ps1 -OutFile C:\SessionRecording\Scripts\script_c.ps1
      Invoke-WebRequest -URI https://github.com/aws-samples/appstream-session-recording/raw/main/variables.ps1 -OutFile C:\SessionRecording\Scripts\variables.ps1
      Invoke-WebRequest -URI https://github.com/aws-samples/appstream-session-recording/raw/main/config.json -OutFile C:\AppStream\SessionScripts\config.json
      

    4. Close the PowerShell terminal.
  4. To edit the variables.ps1 file with your own values:
    1. From the image builder desktop, choose Start in the Windows taskbar.
    2. Open the context (right-click) menu for Windows PowerShell ISE, and then choose Run as Administrator.
    3. Choose File, then Open. Navigate to the folder C:\SessionRecording\Scripts\ and open the file variables.ps1.
    4. Edit the name and the Region of the S3 bucket with the values returned by AWS CloudFormation in the Outputs tab. You can also customize the number of frames per second, and the maximum duration in seconds of each video file. Save the file.
    5. Save and close the file.
  5. To download the latest FFmpeg and PsExec executables to the image builder:
    1. From the image builder desktop, open the Firefox desktop icon.
    2. Navigate to the URL https://www.gyan.dev/ffmpeg/builds/ffmpeg-release-github and choose the link that contains essentials_build.zip to download FFmpeg. Choose Open to download and extract the ZIP archive. Copy the file ffmpeg.exe in the bin folder of the ZIP archive to C:\SessionRecording\Bin\.

      Note: FFmpeg only provides source code and compiled packages are available at third-party locations. If the link above is invalid, go to the FFmpeg download page and follow the instructions to download the latest release build for Windows.

    3. Navigate to the URL https://download.sysinternals.com/files/PSTools.zip to download PsExec. Choose Open to download and extract the ZIP archive. Copy the file PsExec64.exe to C:\SessionRecording\Bin\. You must agree with the license terms, because the solution in this blog post automatically accepts them.
    4. Close Firefox.

Step 4: Specify an application to publish and create an image

In this step, you publish Firefox on your image builder and create an AppStream 2.0 custom image. I chose Firefox because it’s easy to test later in the procedure. You can choose other or additional applications to publish, if needed.

To specify the application to publish and create the image

  1. From the image builder desktop, open the Image Assistant icon available on the desktop. Image Assistant guides you through the image creation process.
  2. In 1. Add Apps:
    1. Choose + Add App.
    2. Enter the location C:\Program Files (x86)\Mozilla Firefox\firefox.exe to add Firefox.
    3. Choose Open. Keep the default settings and choose Save.
    4. Choose Next multiple times until you see 4. Optimize.
  3. In 4. Optimize:
    1. Choose Launch.
    2. Choose Continue until you can see 5. Configure Image.
  4. In 5. Configure Image:
    1. For Name, enter session-recording for your image name.
    2. Choose Next.
  5. In 6. Review:
    1. Choose Disconnect and Create Image.
  6. Back in the AppStream 2.0 console:
    1. Choose Images in the left pane, and then choose the Image Registry tab.
    2. Change All Images to Private and shared with others. You will see your new AppStream 2.0 image.
    3. Wait until the image is in the Available state. This can take more than 30 minutes.

Step 5: Create an AppStream 2.0 fleet

Next, create an AppStream 2.0 fleet that consists of streaming instances that run your custom image.

To create the AppStream 2.0 fleet

  1. In the left pane of the AppStream 2.0 console, choose Fleets, and then choose Create Fleet.
  2. In Step 1: Provide Fleet Details:
    1. For Name, enter session-recording-fleet.
    2. Choose Next.
  3. In Step 2: Choose an Image:
    1. Select the name of the custom image that you created with the image builder.
    2. Choose Next.
  4. In Step 3: Configure Fleet:
    1. For Instance Type, select stream.standard.medium.
    2. For Fleet Type, choose Always-on.
    3. For Stream view, you can choose to stream either the applications or the entire desktop.
    4. For IAM role, select the IAM role.
    5. Keep the defaults for all other parameters, and choose Next.
  5. In Step 4: Configure Network:
    1. Choose Default Internet Access to provide internet access to your image builder.
    2. Select the VPC, the two subnets, and the security group.
    3. Choose Next.
  6. In Step 5: Review, choose Create.
  7. Wait until the fleet is in the Running state.

Step 6: Create an AppStream 2.0 stack

Create an AppStream 2.0 stack and associate it with the fleet that you just created.

To create the AppStream 2.0 stack

  1. In the left pane of the AppStream 2.0 console, choose Stacks, and then choose Create Stack.
  2. In Step 1: Stack Details:
    1. For Name, enter session-recording-stack.
    2. For Fleet, select the fleet that you created.
  3. Then follow the on-screen instructions and keep the defaults for all other parameters until the stack is created.

Step 7: Create a user in the AppStream 2.0 user pool

The AppStream 2.0 user pool provides a simplified way to manage access to applications for your users. In this step, you create a user in the user pool that you will use later in the procedure to test the solution.

To create the user in the AppStream 2.0 user pool

  1. In the left pane of the AppStream 2.0 console, choose User Pool, and then choose Create User.
  2. Enter your email address, first name, and last name. Choose Create User.
  3. Select the user you just created. Choose Actions, and then choose Assign stack.
  4. Select the stack, and then choose Assign stack.

Step 8: Test the solution

Now, sign in to AppStream 2.0 with the user that you just created, launch a streaming session, and check that the session recordings are delivered to Amazon S3.

To launch a streaming session and test the solution

  1. AppStream 2.0 sends you a notification email. Connect to the sign in portal by entering the information included in the notification email, and set a permanent password.
  2. Sign in to AppStream 2.0 by entering your email address and the permanent password.
  3. After you sign in, you can view the application catalog. Choose Firefox to launch a Firefox window and browse any websites you’d like.
  4. Choose the user icon at the top-right corner, and then choose Logout to end the session.

In the Amazon S3 console, navigate to the S3 bucket to browse the session recordings. For the session you just terminated, you can find one text file that contains user and instance metadata, and one or more video files that you can download and play with a media player like VLC.

Step 9: Clean up resources

You can now delete the two CloudFormation stacks to clean up the resources that were just created.

To clean up resources

  1. To delete the image builder:
    1. In the left pane of the AppStream 2.0 console, choose Images, and then choose Image Builder.
    2. Select the image builder. Choose Actions, then choose Delete.
  2. To delete the stack:
    1. In the left pane of the AppStream 2.0 console, choose Stacks.
    2. Select the image builder. Choose Actions, then choose Disassociate Fleet. Choose Disassociate to confirm.
    3. Choose Actions, then choose Delete.
  3. To delete the fleet:
    1. In the left pane of the AppStream 2.0 console, choose Fleets.
    2. Select the fleet. Choose Actions, then choose Stop. Choose Stop to confirm.
    3. Wait until the fleet is in the Stopped state.
    4. Choose Actions, then choose Delete.
  4. To disable the user in the user pool:
    1. In the left pane of the AppStream 2.0 console, choose User Pool.
    2. Select the user. Choose Actions, then choose Disable user. Choose Disable User to confirm.
  5. Empty the S3 bucket that CloudFormation created (see How do I empty an S3 bucket?). Repeat the same operation with the buckets that AppStream 2.0 created, whose names start with appstream-settings, appstream-logs and appstream2.
  6. Delete the CloudFormation stack on the AWS CloudFormation console (see Deleting a stack on the AWS CloudFormation console).

Conclusion

In this blog post, I showed you a way to record AppStream 2.0 sessions to video files for administrative access auditing, troubleshooting, or quality assurance. While this blog post focuses on Amazon AppStream 2.0, you could adapt and deploy the solution in Amazon Workspaces or in Amazon Elastic Compute Cloud (Amazon EC2) Windows instances.

For a deep-dive explanation of how the solution scripts function, you can refer to the GitHub repository that contains the solution artifacts.

If you have feedback about this post, submit comments in the Comments section below. If you have questions about this post, start a new thread on the Amazon AppStream 2.0 forum or contact AWS Support.

Want more AWS Security how-to content, news, and feature announcements? Follow us on Twitter.

Author

Nicolas Malaval

Nicolas is a Solution Architect for Amazon Web Services. He lives in Paris and helps our healthcare customers in France adopt cloud technology and innovate with AWS. Before that, he spent three years as a Consultant for AWS Professional Services, working with enterprise customers.

BBVA: Helping Global Remote Working with Amazon AppStream 2.0

Post Syndicated from Joe Luis Prieto original https://aws.amazon.com/blogs/architecture/bbva-helping-global-remote-working-with-amazon-appstream-2-0/

This post was co-written with Javier Jose Pecete, Cloud Security Architect at BBVA, and Javier Sanz Enjuto, Head of Platform Protection – Security Architecture at BBVA.

Introduction

Speed and elasticity are key when you are faced with unexpected scenarios such as a massive employee workforce working from home or running more workloads on the public cloud if data centers face staffing reductions. AWS customers can instantly benefit from implementing a fully managed turnkey solution to help cope with these scenarios.

Companies not only need to use technology as the foundation to maintain business continuity and adjust their business model for the future, but they also must work to help their employees adapt to new situations.

About BBVA

BBVA is a customer-centric, global financial services group present in more than 30 countries throughout the world, has more than 126,000 employees, and serves more than 78 million customers.

Founded in 1857, BBVA is a leader in the Spanish market as well as the largest financial institution in Mexico. It has leading franchises in South America and the Sun Belt region of the United States and is the leading shareholder in Turkey’s Garanti BBVA.

The challenge

BBVA implemented a global remote working plan that protects customers and employees alike, including a significant reduction of the number of employees working in its branch offices. It also ensured continued and uninterrupted operations for both consumer and business customers by strengthening digital access to its full suite of services.

Following the company’s policies and adhering to new rules announced by national authorities in the last weeks, more than 86,000 employees from across BBVA’s international network of offices and its central service functions now work remotely.

BBVA, subject to a set of highly regulated requirements, and was looking for a global architecture to accommodate remote work. The solution needed to be fast to implement, adaptable to scale out gradually in the various countries in which it operates, and able to meet its operational, security, and regulatory requirements.

The architecture

BBVA selected Amazon AppStream 2.0 for particular use cases of applications that, due to their sensitivity, are not exposed to the internet (such as financial, employee, and security applications). Having had previous experience with the service, BBVA chose AppStream 2.0 to accommodate the remote work experience.

AppStream 2.0 is a fully managed application streaming service that provides users with instant access to their desktop applications from anywhere, regardless of what device they are using.

AppStream 2.0 works with IT environments, can be managed through the AWS SDK or console, automatically scales globally on demand, and is fully managed on AWS. This means there is no hardware or software to deploy, patch, or upgrade.

AppStream 2.0 can be managed through the AWS SDK (1)

  1. The streamed video and user inputs are sent over HTTPS and are SSL-encrypted between the AppStream 2.0 instance executing your applications, and your end users.
  2. Security groups are used to control network access to the customer VPC.
  3. AppStream 2.0 streaming instance access to the internet is through the customer VPC.

AppStream 2.0 fleets are created by use case to apply security restrictions depending on data sensitivity. Setting clipboard, file transfer, or print to local device options, the fleets control the data movement to and from employees’ AppStream 2.0 streaming sessions.

BBVA relies on a proprietary service called Heimdal to authenticate employees through the corporate identity provider. Heimdal calls the AppStream 2.0 API CreateStreamingURL operation to create a temporary URL to start a streaming session for the specified user, and tries to abstract the user from the service using:

  • FleetName to connect the most appropriate fleet based on the user’s location (BBVA has fleets deployed in Europe and America to improve the user’s experience.)
  • ApplicationId to launch the proper application without having to use an intermediate portal
  • SessionContext in situations where, for instance, the authentication service generates a token and needs to be forwarded to a browser application and injected as a session cookie

BBVA uses AWS Transit Gateway to build a hub-and-spoke network topology (2)

To simplify its overall network architecture, BBVA uses AWS Transit Gateway to build a hub-and-spoke network topology with full control over network routing and security.

There are situations where the application streamed in AppStream 2.0 needs to connect:

  1. On-premises, using AWS Direct Connect plus VPN providing an IPsec-encrypted private connection
  2. To the Internet through an outbound VPC proxy with domain whitelisting and content filtering to control the information and threats in the navigation of the employee

AppStream 2.0 activity is logged into a centralized repository support by Amazon S3 for detecting unusual behavior patterns and by regulatory requirements.

Conclusion

BBVA built a global solution reducing implementation time by 90% compared to on-premises projects, and is meeting its operational and security requirements. As well, the solution is helping with the company’s top concern: protecting the health and safety of its employees.

How to use Amazon AppStream 2.0 to reduce your bastion host attack surface

Post Syndicated from Chaim Landau original https://aws.amazon.com/blogs/security/how-to-use-amazon-appstream-2-0-to-reduce-your-bastion-host-attack-surface/

July 16, 2020: This post was originally published May 2, 2018, and has been updated to clarify some AppStream 2.0 details.


Update: To help protect their assets, many security-conscious enterprises require their system administrators to go through a “bastion” (or “jump”) host to gain administrative access to backend systems in protected or sensitive network segments.

A bastion host is a special-purpose instance that hosts a minimal number of administrative applications, such as RDP for Windows or Putty for Linux-based distributions. All other unnecessary services are removed. The host is typically placed in a segregated network (or “DMZ”), and is often protected with multi-factor authentication (MFA) and monitored with auditing tools. And most enterprises require that the access trail to the bastion host be auditable.

In this post, I demonstrate the use of Amazon AppStream 2.0 as a hardened and auto-scaled bastion host solution by providing only the necessary tools to system administrators that need access to a protected network.

Prerequisites

  • A Virtual Private Cloud (VPC) with a dedicated subnet for AppStream 2.0.
  • An existing Active Directory (AD) domain. This may be on premises, on AWS EC2 for Windows, or AWS Directory Service for Microsoft Active Directory used as a user directory.
  • Active Directory Federation Services (ADFS).
  • A Linux or Windows instance for which AppStream 2.0 will be acting as a bastion host.

Solution overview

Amazon AppStream 2.0 is a fully managed application streaming service that provides users instant access to their desktop applications from anywhere by using an HTML5-compatible desktop browser. When a user requests access to an application, AppStream 2.0 uses a base image to deploy a streaming instance and destroys the instance after the user closes their session. This ensures the same consistent experience during each logon.

You can use AppStream 2.0 as a bastion solution to enable your system administrators to manage their environment without giving them a full bastion host. Because AppStream 2.0 freshly builds instances each time a user requests access, a compromised instance will only last for the duration of a user session. As soon as the user closes their session and the Disconnect Timeout period is reached, AppStream 2.0 terminates the instance and, with it, you’ve reduced your risks of compromised instances.

You will also potentially reduce your costs because AppStream 2.0 has built-in auto-scaling to increase and decrease capacity based on user demand. It allows you to take advantage of the pay-as-you-go model, where you only pay for what you use.

High-level AppStream 2.0 architecture

The diagram below depicts a high-level AppStream 2.0 architecture used as a bastion host for servers in another VPC.

There are three VPCs shown: AppStream 2.0 VPC, Bastion host VPC, and application VPC. The AppStream 2.0 VPC is an AWS-owned VPC where the AppStream 2.0 maintains its infrastructure. Customers are not responsible for this VPC and have no access to it. AppStream 2.0 builds each streaming instance with two Elastic Network Interfaces (ENI); one in the AppStream 2.0 VPC and one in the VPC where you choose to deploy your AppStream 2.0 instances. The third VPC is the application VPC where you would typically keep your backend servers.

The diagram also depicts the end-user process to access the AppStream 2.0 environment, which works as follow:

  1. Using an HTML5 desktop browser the user logs on to a Single Sign-On URL. This authenticates the user against the corporate directory using SAML 2.0 federation and with optional MFA.
  2. After successful authentication, the user will see a list of provisioned applications.
  3. The user can launch applications, such as RDP and Putty, which are only visible within the browser and with its underlying OS hidden. The user is then able to connect to the backend systems over the ports that were opened through security groups. The user logs off and AppStream 2.0 destroys the instance used for the session.

 

Architecture diagram

Figure 1: Architecture diagram

Step-by-step instructions

This walk-through assumes you have created the following resources as prerequisites.

  • A single VPC with a /23 CIDR range and two private subnets in two AZs.

    Note: “private” subnet refers to a subnet that has no internet gateway (IGW) attached.

    • Bastion Subnets — used for the AppStream 2.0 instances that will be hosting the bastion applications.
    • Apps Subnets — used for the servers for which the AppStream 2.0 instances will be acting as a bastion host.

      Screen shot of bastion and apps subnets

      Figure 2: Screen shot of bastion and apps subnets

  • A peering connection to a VPC where the corporate Active Directory resides and with updated routing tables. This is only necessary if your AD resides in a different VPC.
  • Two EC2 instances with private IP addresses in the app subnet.

Phase 1: Create the DHCP Options Set

For the AppStream 2.0 instances to be able to join the corporate domain, they need to have their DNS entries point to the corporate domain controller(s). To accomplish this, you need to create a DHCP Options Set and assign it to the VPC:

  1. Sign in to the AWS console, and then select VPC Dashboard > DHCP Option Sets > Create DHCP options set.
  2. Give the DHCP Options Set a name, enter the domain name and DNS server(s) of your corporate domain controller(s), and then select Yes, Create.
  3. Select your VPC Dashboard > your VPC > Actions > Edit DHCP Options Set.
  4. Select the DHCP Options Set created in the previous step, and then select Save.

    The "Edit DHCP Options Set" dialog

    Figure 3: The “Edit DHCP Options Set” dialog

Phase 2: Create the AppStream 2.0 Stack

An AppStream 2.0 stack consists of a fleet, user access policies, and storage configuration. To create a stack, follow these steps:

  1. Sign in to the AWS console and select AppStream 2.0 > Stack > Create Stack.
  2. Give the stack a name, and then select Next.
  3. Enable Home Folders, if you want persistent storage, and then select Review.

    The "Enable Home Folders" dialog

    Figure 4: The “Enable Home Folders” dialog

  4. Select Create.

Phase 3: Create the AppsStream 2.0 Directory Configuration

First create a directory configuration so you can join the AppStream 2.0 instances to an Organizational Unit (OU) in your corporate directory.

Note: AppStream 2.0 instances must be placed in an OU and can’t reside in the Computer Container.

To create a directory configuration, follow these steps:

  1. Sign in to the AWS console and select AppStream 2.0 > Directory Configs > Create Directory Config.
  2. Enter the following Directory Config information:
    • Directory name: The FQDN of your corporate domain.
    • Service Account Name: The account AppStream 2.0 uses to join the instances to the corporate domain. The required service account privileges are documented here.
    • Organizational Unit (OU): The OUs where AppStream 2.0 will create your instances. You can add additional OUs by clicking the plus (+) sign.
  3. Select Next, and then select Create.

Create Security Groups

Now, create AWS security groups for your AppStream 2.0 instances and backend servers.

BastionHostSecurityGroup

For your AppStream 2.0 instances, you must attach a “BastionHostSecurityGroup” in order to communicate to the backend servers. This security group is only used as a “source” by the security groups the backend servers are attached to and, therefore, they don’t require any inbound ports to be opened.

To create a security group, follow these steps:

  1. Sign in to the AWS console and select VPC > Security Groups > Create Security Group.
  2. Give your “BastionHostSecurityGroup” Security Group a name, select the VPC where you will place the AppStream 2.0 instances, and then select Yes, Create.

BastionHostAccessSecurityGroup

For your backend servers, you must attach a “BastionHostAccessSecurityGroup” that allows incoming traffic from the AppStream 2.0 instance. Unlike the “BastionHostSecurityGroup”, this one requires open inbound ports.

  1. Sign in to the AWS console and select VPC > Security Groups > Create Security Group.
  2. Give your “BastionHostAccessSecurityGroup” security group a name, select the correct VPC, and then select Yes, Create.
  3. In the Security Group console, select the newly created security group, select the Inbound Rule tab, and then select Edit.
  4. Add rules to open port 3389 and 22, use the previously-created security group as the source, and then select Save.
    Opening ports 3389 and 22

    Figure 5: Opening ports 3389 and 22

    Note: In addition to security groups, you can place Network ACLs (NACLs) around the subnet you use for AppStream 2.0 as an additional layer of security. The main differences between security groups and NACLs are that security groups are mandatory and you apply them to the instance level, while you apply NACLs to the subnet level and are optional. Another difference worth pointing out is that NACLs are “stateless” while security groups are “stateful.” This means that any port allowed inbound via NACLs will need a corresponding outbound rule. For more information on NACLs, refer to this documentation.

Phase 4: Build the AppStream 2.0 Image

An AppStream 2.0 image contains applications that you can stream to users. AppStream 2.0 uses the image to launch streaming instances that are part of an AppStream 2.0 fleet.

Once you have created the stack, create a custom image to make custom applications available to the users:

  1. Sign in to the AWS console and select AppStream 2.0 > Images > Image Builder > Launch Image Builder.
  2. Choose the image you want to use as a starting point, and then select Next. For this example, I chose a generic image from the General Purpose stock.

    Choosing an image

    Figure 6: Choosing an image

  3. Give your image a name, choose the instance family, and then select Next.
  4. Choose the VPC and subnet you want to deploy the AppStream 2.0 instances in.
  5. Select the security group you created for the AppStream 2.0 instances.
  6. Select the directory configuration you created, the OU you want your AppStream 2.0 instances to reside in, and then select Review.
  7. Select Launch.
  8. Once the image is built and in a running state, select the image, and then select Connect. This will open a new browser tab where you’ll be able to connect to and manage the image.
  9. Select Administrator and log in.

    Log in as a local administrator

    Figure 7: Log in as a local administrator

  10. Once logged in as administrator, select the Image Assistant shortcut on the desktop.

    The Image Assistant shortcut on the desktop

    Figure 8: The Image Assistant shortcut on the desktop

  11. Add all the applications you want to make available to your users for streaming, and then select Next.

    Note: If you need to upload installation or configuration files, you can use the My Files option in the Control menu. Any files uploaded through this method will show up under the X: drive on the Image Builder.

     

    The "Control" menu

    Figure 9: The “Control” menu

  12. If you want to test the applications as a non-privileged user, follow the on-screen instructions to switch the user. Otherwise, select Next.

    "Switch User" on-screen instructions

    Figure 10: “Switch User” on-screen instructions

  13. Select Launch to have the Image Assistant optimize the applications.
  14. Give the image a name, and then select Next.
  15. Select Disconnect and Create Image.
  16. Go back to the AppStream 2.0 console and wait for the “snapshotting” to complete and for the image to be in an available state before continuing to the next step.

Phase 5: Create the AppStream 2.0 Fleet

Once you create your Stack and image, you need to create a Fleet and associate it with your Stack.

AppStream 2.0 fleets consist of streaming instances that run the image that you specify. The fleet type determines when your instances run and how you pay for them. You can specify a fleet type when you create a fleet, and you can’t change them once they’ve been created.

To create a fleet, follow these steps:

  1. Sign in to the AWS console and select AppStream 2.0 > Fleets > Create Fleet.
  2. Give your fleet a name, and then select Next.
  3. Select the newly created image, and then select Next.
  4. Choose your preferred settings, and then select Next.

    Important: Pay special attention to the Fleet capacity value. Fleet capacity determines the number of running instances you have at any given time, and it affects your costs.

     

    The "Fleet capacity" dialog

    Figure 11: The “Fleet capacity” dialog

  5. Select your VPC, subnet(s), security Group(s), Active Directory settings, and then select Next.
  6. Review the information, and then select Create.

    Review your settings

    Figure 12: Review your settings

Associate the fleet with the stack

Follow these steps:

  1. Sign in to the AWS console and select AppStream 2.0 > Stacks.
  2. Select the stack, select Actions, and then select Associate Fleet.
  3. Select the fleet, and then select Associate.

Phase 6: Configure ADFS for AppStream 2.0

To have users authenticate against the corporate directory prior to accessing AppStream 2.0, use a Single Sign-On solution. For this demo, I use ADFS. If you choose another solution, follow the instructions that come with the solution. For help with setting up ADFS with AppStream 2.0, review Enabling Identify Federation with ADSF and Amazon Appstream 2.0.

Note: If you use AWS Directory Service for Microsoft AD (AWS Managed Microsoft AD) as your user directory, you can use ADFS by following the ADFS set-up instructions in the blog on How to Enable Your Users to Access Office 365 with AWS Managed Microsoft AD Credentials.

End User Experience

This section shows you what the AppStream 2.0 end user experience is like when connecting to backend Windows and Linux instances.

Note: Make sure you have backend servers to connect to, as indicated in the prerequisites.

Process

  1. Access the ADFS URL that you created as part of the ADFS setup.
  2. Sign in using your corporate credentials.
  3. Select Remote Desktop from the list of applications.
  4. Enter your corporate credentials.
  5. Enter the private IP address of the backend windows instance you want to remote in to.
    Enter the private IP address

    Figure 13: Enter the private IP address

    You’re now logged on to the backend Windows instance through AppStream 2.0.

  6. To test in Linux, open putty. Select the Launch app icon in the Control menu, and then select putty.

    The "Control" menu showing putty

    Figure 14: The “Control” menu showing putty

  7. Provide the private IP address of a backend Linux host you want to connect to, and then select Open.

    Note: For putty to connect to a Linux instance on AWS, you will need to provide a KeyPair. For information on how to configure putty and KeyPairs, refer to this documentation.

You’re now logged on to a backend Linux host through AppStream 2.0.

Monitoring

You can monitor AppStream 2.0 use by default with the following AWS monitoring services.

  • Amazon CloudWatch is a monitoring service for AWS cloud resources. You can use CloudWatch to collect and track metrics, collect and monitor log files, set alarms, and automatically react to changes in your AWS resources. For more information, refer to this documentation. Here’s a sample CloudWatch metric showing in-use capacity was 100% at 14:30, which indicates the Fleet capacity may need to be adjusted.

    An example CoudWatch metric

    Figure 15: An example CloudWatch metric

  • AWS CloudTrail is a service that enables governance, compliance, operational auditing, and risk auditing of your AWS account. With CloudTrail, you can log, continuously monitor, and retain account activity related to actions across your AWS infrastructure. For more information, refer to this documentation. Here’s a sample CloudTrail event. For example, from this event you can see that user Bob logged on to AppStream 2.0 on March 4, 2018, and you can see his source IP.

    An example CloudTrail event

    Figure 16: An example CloudTrail event

Summary

Amazon AppStream 2.0 is a cost-effective way to provide administrators with a secure and auditable method to access their backend environments.

The AppStream 2.0 built-in auto-scaling feature offers a pay-as-you-go model, where the number of instances running is based on user demand. This allows you to keep costs down without compromising availability. Another cost-saving benefit of AppStream 2.0 is its underlying infrastructure being managed and maintained by AWS, so you can deploy AppStream 2.0 with minimal effort.

AppStream 2.0 allows you to securely deliver applications from AWS as encrypted pixel frames to an end user device. By default, AppStream 2.0 enables the applications that you specify in your image to launch other applications and executable files on the image builder and fleet instance. This ensures that applications with dependencies on other applications (for example, an application that launches the browser to navigate to a product website) function as expected. Make sure that you configure your administrative controls, security groups, and other security software to grant users the minimum permissions required to access resources and transfer data between their local computers and fleet instances. You can use application control software, such as Microsoft AppLocker, and policies to control which applications and files your users can run. Application control software and policies help you control the executable files, scripts, Windows installer files, dynamic-link libraries, and application packages that your users can run on AppStream 2.0 image builders and fleet instances. For more information, see Using Microsoft AppLocker to manage application experience on Amazon AppStream. To learn more about how to secure your streaming instances, see Security in Amazon AppStream 2.0.

Another security benefit of AppStream 2.0 is that it destroys streaming instances after each use, reducing risks. This is a good mitigation strategy against compromised instances, as the lifespan of an instance is limited to the length of a user’s session.

AppStream 2.0 support for SAML provides yet another layer of security, allowing you to restrict access to SAML-federated URLs from corporate networks only, as well as the ability to enforce multi-factor authentication (MFA).

You can monitor the AppStream 2.0 environment through the use of AWS CloudTrail and Amazon CloudWatch, allowing you to monitor and trace the usage of AppStream 2.0.

For all of these reasons, AppStream 2.0 makes for a uniquely attractive bastion host solution.

For more information on the technologies mentioned in this blog, see the links below:

If you have comments about this post, submit them in the Comments section below. If you have questions about anything in this post, start a new thread on the Amazon AppStream 2.0 forum or contact AWS Support.

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Chaim Landau

Chaim Landau is a Senior Cloud Infrastructure Architect based out of New York City. Chaim joined AWS in 2016 and assists large enterprise customers with designing and developing their AWS architectures. In his free time, he enjoys running, cycling, skiing, and reading.