All posts by Arun Gupta

Manage Kubernetes Clusters on AWS Using CoreOS Tectonic

Post Syndicated from Arun Gupta original https://aws.amazon.com/blogs/compute/kubernetes-clusters-aws-coreos-tectonic/

There are multiple ways to run a Kubernetes cluster on Amazon Web Services (AWS). The first post in this series explained how to manage a Kubernetes cluster on AWS using kops. This second post explains how to manage a Kubernetes cluster on AWS using CoreOS Tectonic.

Tectonic overview

Tectonic delivers the most current upstream version of Kubernetes with additional features. It is a commercial offering from CoreOS and adds the following features over the upstream:

  • Installer
    Comes with a graphical installer that installs a highly available Kubernetes cluster. Alternatively, the cluster can be installed using AWS CloudFormation templates or Terraform scripts.
  • Operators
    An operator is an application-specific controller that extends the Kubernetes API to create, configure, and manage instances of complex stateful applications on behalf of a Kubernetes user. This release includes an etcd operator for rolling upgrades and a Prometheus operator for monitoring capabilities.
  • Console
    A web console provides a full view of applications running in the cluster. It also allows you to deploy applications to the cluster and start the rolling upgrade of the cluster.
  • Monitoring
    Node CPU and memory metrics are powered by the Prometheus operator. The graphs are available in the console. A large set of preconfigured Prometheus alerts are also available.
  • Security
    Tectonic ensures that cluster is always up to date with the most recent patches/fixes. Tectonic clusters also enable role-based access control (RBAC). Different roles can be mapped to an LDAP service.
  • Support
    CoreOS provides commercial support for clusters created using Tectonic.

Tectonic can be installed on AWS using a GUI installer or Terraform scripts. The installer prompts you for the information needed to boot the Kubernetes cluster, such as AWS access and secret key, number of master and worker nodes, and instance size for the master and worker nodes. The cluster can be created after all the options are specified. Alternatively, Terraform assets can be downloaded and the cluster can be created later. This post shows using the installer.

CoreOS License and Pull Secret

Even though Tectonic is a commercial offering, a cluster for up to 10 nodes can be created by creating a free account at Get Tectonic for Kubernetes. After signup, a CoreOS License and Pull Secret files are provided on your CoreOS account page. Download these files as they are needed by the installer to boot the cluster.

IAM user permission

The IAM user to create the Kubernetes cluster must have access to the following services and features:

  • Amazon Route 53
  • Amazon EC2
  • Elastic Load Balancing
  • Amazon S3
  • Amazon VPC
  • Security groups

Use the aws-policy policy to grant the required permissions for the IAM user.

DNS configuration

A subdomain is required to create the cluster, and it must be registered as a public Route 53 hosted zone. The zone is used to host and expose the console web application. It is also used as the static namespace for the Kubernetes API server. This allows kubectl to be able to talk directly with the master.

The domain may be registered using Route 53. Alternatively, a domain may be registered at a third-party registrar. This post uses a kubernetes-aws.io domain registered at a third-party registrar and a tectonic subdomain within it.

Generate a Route 53 hosted zone using the AWS CLI. Download jq to run this command:

ID=$(uuidgen) && \
aws route53 create-hosted-zone \
--name tectonic.kubernetes-aws.io \
--caller-reference $ID \
| jq .DelegationSet.NameServers

The command shows an output such as the following:

[
  "ns-1924.awsdns-48.co.uk",
  "ns-501.awsdns-62.com",
  "ns-1259.awsdns-29.org",
  "ns-749.awsdns-29.net"
]

Create NS records for the domain with your registrar. Make sure that the NS records can be resolved using a utility like dig web interface. A sample output would look like the following:

The bottom of the screenshot shows NS records configured for the subdomain.

Download and run the Tectonic installer

Download the Tectonic installer (version 1.7.1) and extract it. The latest installer can always be found at coreos.com/tectonic. Start the installer:

./tectonic/tectonic-installer/$PLATFORM/installer

Replace $PLATFORM with either darwin or linux. The installer opens your default browser and prompts you to select the cloud provider. Choose Amazon Web Services as the platform. Choose Next Step.

Specify the Access Key ID and Secret Access Key for the IAM role that you created earlier. This allows the installer to create resources required for the Kubernetes cluster. This also gives the installer full access to your AWS account. Alternatively, to protect the integrity of your main AWS credentials, use a temporary session token to generate temporary credentials.

You also need to choose a region in which to install the cluster. For the purpose of this post, I chose a region close to where I live, Northern California. Choose Next Step.

Give your cluster a name. This name is part of the static namespace for the master and the address of the console.

To enable in-place update to the Kubernetes cluster, select the checkbox next to Automated Updates. It also enables update to the etcd and Prometheus operators. This feature may become a default in future releases.

Choose Upload “tectonic-license.txt” and upload the previously downloaded license file.

Choose Upload “config.json” and upload the previously downloaded pull secret file. Choose Next Step.

Let the installer generate a CA certificate and key. In this case, the browser may not recognize this certificate, which I discuss later in the post. Alternatively, you can provide a CA certificate and a key in PEM format issued by an authorized certificate authority. Choose Next Step.

Use the SSH key for the region specified earlier. You also have an option to generate a new key. This allows you to later connect using SSH into the Amazon EC2 instances provisioned by the cluster. Here is the command that can be used to log in:

ssh –i <key> [email protected]<ec2-instance-ip>

Choose Next Step.

Define the number and instance type of master and worker nodes. In this case, create a 6 nodes cluster. Make sure that the worker nodes have enough processing power and memory to run the containers.

An etcd cluster is used as persistent storage for all of Kubernetes API objects. This cluster is required for the Kubernetes cluster to operate. There are three ways to use the etcd cluster as part of the Tectonic installer:

  • (Default) Provision the cluster using EC2 instances. Additional EC2 instances are used in this case.
  • Use an alpha support for cluster provisioning using the etcd operator. The etcd operator is used for automated operations of the etcd master nodes for the cluster itself, in addition to for etcd instances that are created for application usage. The etcd cluster is provisioned within the Tectonic installer.
  • Bring your own pre-provisioned etcd cluster.

Use the first option in this case.

For more information about choosing the appropriate instance type, see the etcd hardware recommendation. Choose Next Step.

Specify the networking options. The installer can create a new public VPC or use a pre-existing public or private VPC. Make sure that the VPC requirements are met for an existing VPC.

Give a DNS name for the cluster. Choose the domain for which the Route 53 hosted zone was configured earlier, such as tectonic.kubernetes-aws.io. Multiple clusters may be created under a single domain. The cluster name and the DNS name would typically match each other.

To select the CIDR range, choose Show Advanced Settings. You can also choose the Availability Zones for the master and worker nodes. By default, the master and worker nodes are spread across multiple Availability Zones in the chosen region. This makes the cluster highly available.

Leave the other values as default. Choose Next Step.

Specify an email address and password to be used as credentials to log in to the console. Choose Next Step.

At any point during the installation, you can choose Save progress. This allows you to save configurations specified in the installer. This configuration file can then be used to restore progress in the installer at a later point.

To start the cluster installation, choose Submit. At another time, you can download the Terraform assets by choosing Manually boot. This allows you to boot the cluster later.

The logs from the Terraform scripts are shown in the installer. When the installation is complete, the console shows that the Terraform scripts were successfully applied, the domain name was resolved successfully, and that the console has started. The domain works successfully if the DNS resolution worked earlier, and it’s the address where the console is accessible.

Choose Download assets to download assets related to your cluster. It contains your generated CA, kubectl configuration file, and the Terraform state. This download is an important step as it allows you to delete the cluster later.

Choose Next Step for the final installation screen. It allows you to access the Tectonic console, gives you instructions about how to configure kubectl to manage this cluster, and finally deploys an application using kubectl.

Choose Go to my Tectonic Console. In our case, it is also accessible at http://cluster.tectonic.kubernetes-aws.io/.

As I mentioned earlier, the browser does not recognize the self-generated CA certificate. Choose Advanced and connect to the console. Enter the login credentials specified earlier in the installer and choose Login.

The Kubernetes upstream and console version are shown under Software Details. Cluster health shows All systems go and it means that the API server and the backend API can be reached.

To view different Kubernetes resources in the cluster choose, the resource in the left navigation bar. For example, all deployments can be seen by choosing Deployments.

By default, resources in the all namespace are shown. Other namespaces may be chosen by clicking on a menu item on the top of the screen. Different administration tasks such as managing the namespaces, getting list of the nodes and RBAC can be configured as well.

Download and run Kubectl

Kubectl is required to manage the Kubernetes cluster. The latest version of kubectl can be downloaded using the following command:

curl -LO https://storage.googleapis.com/kubernetes-release/release/$(curl -s https://storage.googleapis.com/kubernetes-release/release/stable.txt)/bin/darwin/amd64/kubectl

It can also be conveniently installed using the Homebrew package manager. To find and access a cluster, Kubectl needs a kubeconfig file. By default, this configuration file is at ~/.kube/config. This file is created when a Kubernetes cluster is created from your machine. However, in this case, download this file from the console.

In the console, choose admin, My Account, Download Configuration and follow the steps to download the kubectl configuration file. Move this file to ~/.kube/config. If kubectl has already been used on your machine before, then this file already exists. Make sure to take a backup of that file first.

Now you can run the commands to view the list of deployments:

~ $ kubectl get deployments --all-namespaces
NAMESPACE         NAME                                    DESIRED   CURRENT   UP-TO-DATE   AVAILABLE   AGE
kube-system       etcd-operator                           1         1         1            1           43m
kube-system       heapster                                1         1         1            1           40m
kube-system       kube-controller-manager                 3         3         3            3           43m
kube-system       kube-dns                                1         1         1            1           43m
kube-system       kube-scheduler                          3         3         3            3           43m
tectonic-system   container-linux-update-operator         1         1         1            1           40m
tectonic-system   default-http-backend                    1         1         1            1           40m
tectonic-system   kube-state-metrics                      1         1         1            1           40m
tectonic-system   kube-version-operator                   1         1         1            1           40m
tectonic-system   prometheus-operator                     1         1         1            1           40m
tectonic-system   tectonic-channel-operator               1         1         1            1           40m
tectonic-system   tectonic-console                        2         2         2            2           40m
tectonic-system   tectonic-identity                       2         2         2            2           40m
tectonic-system   tectonic-ingress-controller             1         1         1            1           40m
tectonic-system   tectonic-monitoring-auth-alertmanager   1         1         1            1           40m
tectonic-system   tectonic-monitoring-auth-prometheus     1         1         1            1           40m
tectonic-system   tectonic-prometheus-operator            1         1         1            1           40m
tectonic-system   tectonic-stats-emitter                  1         1         1            1           40m

This output is similar to the one shown in the console earlier. Now, this kubectl can be used to manage your resources.

Upgrade the Kubernetes cluster

Tectonic allows the in-place upgrade of the cluster. This is an experimental feature as of this release. The clusters can be updated either automatically, or with manual approval.

To perform the update, choose Administration, Cluster Settings. If an earlier Tectonic installer, version 1.6.2 in this case, is used to install the cluster, then this screen would look like the following:

Choose Check for Updates. If any updates are available, choose Start Upgrade. After the upgrade is completed, the screen is refreshed.

This is an experimental feature in this release and so should only be used on clusters that can be easily replaced. This feature may become a fully supported in a future release. For more information about the upgrade process, see Upgrading Tectonic & Kubernetes.

Delete the Kubernetes cluster

Typically, the Kubernetes cluster is a long-running cluster to serve your applications. After its purpose is served, you may delete it. It is important to delete the cluster as this ensures that all resources created by the cluster are appropriately cleaned up.

The easiest way to delete the cluster is using the assets downloaded in the last step of the installer. Extract the downloaded zip file. This creates a directory like <cluster-name>_TIMESTAMP. In that directory, give the following command to delete the cluster:

TERRAFORM_CONFIG=$(pwd)/.terraformrc terraform destroy --force

This destroys the cluster and all associated resources.

You may have forgotten to download the assets. There is a copy of the assets in the directory tectonic/tectonic-installer/darwin/clusters. In this directory, another directory with the name <cluster-name>_TIMESTAMP contains your assets.

Conclusion

This post explained how to manage Kubernetes clusters using the CoreOS Tectonic graphical installer.  For more details, see Graphical Installer with AWS. If the installation does not succeed, see the helpful Troubleshooting tips. After the cluster is created, see the Tectonic tutorials to learn how to deploy, scale, version, and delete an application.

Future posts in this series will explain other ways of creating and running a Kubernetes cluster on AWS.

Arun

Manage Kubernetes Clusters on AWS Using Kops

Post Syndicated from Arun Gupta original https://aws.amazon.com/blogs/compute/kubernetes-clusters-aws-kops/

Any containerized application typically consists of multiple containers. There is a container for the application itself, one for database, possibly another for web server, and so on. During development, its normal to build and test this multi-container application on a single host. This approach works fine during early dev and test cycles but becomes a single point of failure for production where the availability of the application is critical. In such cases, this multi-container application is deployed on multiple hosts. There is a need for an external tool to manage such a multi-container multi-host deployment. Container orchestration frameworks provides the capability of cluster management, scheduling containers on different hosts, service discovery and load balancing, crash recovery and other related functionalities. There are multiple options for container orchestration on Amazon Web Services: Amazon ECS, Docker for AWS, and DC/OS.

Another popular option for container orchestration on AWS is Kubernetes. There are multiple ways to run a Kubernetes cluster on AWS. This multi-part blog series provides a brief overview and explains some of these approaches in detail. This first post explains how to create a Kubernetes cluster on AWS using kops.

Kubernetes and Kops overview

Kubernetes is an open source, container orchestration platform. Applications packaged as Docker images can be easily deployed, scaled, and managed in a Kubernetes cluster. Some of the key features of Kubernetes are:

  • Self-healing
    Failed containers are restarted to ensure that the desired state of the application is maintained. If a node in the cluster dies, then the containers are rescheduled on a different node. Containers that do not respond to application-defined health check are terminated, and thus rescheduled.
  • Horizontal scaling
    Number of containers can be easily scaled up and down automatically based upon CPU utilization, or manually using a command.
  • Service discovery and load balancing
    Multiple containers can be grouped together discoverable using a DNS name. The service can be load balanced with integration to the native LB provided by the cloud provider.
  • Application upgrades and rollbacks
    Applications can be upgraded to a newer version without an impact to the existing one. If something goes wrong, Kubernetes rolls back the change.

Kops, short for Kubernetes Operations, is a set of tools for installing, operating, and deleting Kubernetes clusters in the cloud. A rolling upgrade of an older version of Kubernetes to a new version can also be performed. It also manages the cluster add-ons. After the cluster is created, the usual kubectl CLI can be used to manage resources in the cluster.

Download Kops and Kubectl

There is no need to download the Kubernetes binary distribution for creating a cluster using kops. However, you do need to download the kops CLI. It then takes care of downloading the right Kubernetes binary in the cloud, and provisions the cluster.

The different download options for kops are explained at github.com/kubernetes/kops#installing. On MacOS, the easiest way to install kops is using the brew package manager.

brew update && brew install kops

The version of kops can be verified using the kops version command, which shows:

Version 1.6.1

In addition, download kubectl. This is required to manage the Kubernetes cluster. The latest version of kubectl can be downloaded using the following command:

curl -LO https://storage.googleapis.com/kubernetes-release/release/$(curl -s https://storage.googleapis.com/kubernetes-release/release/stable.txt)/bin/darwin/amd64/kubectl

Make sure to include the directory where kubectl is downloaded in your PATH.

IAM user permission

The IAM user to create the Kubernetes cluster must have the following permissions:

  • AmazonEC2FullAccess
  • AmazonRoute53FullAccess
  • AmazonS3FullAccess
  • IAMFullAccess
  • AmazonVPCFullAccess

Alternatively, a new IAM user may be created and the policies attached as explained at github.com/kubernetes/kops/blob/master/docs/aws.md#setup-iam-user.

Create an Amazon S3 bucket for the Kubernetes state store

Kops needs a “state store” to store configuration information of the cluster.  For example, how many nodes, instance type of each node, and Kubernetes version. The state is stored during the initial cluster creation. Any subsequent changes to the cluster are also persisted to this store as well. As of publication, Amazon S3 is the only supported storage mechanism. Create a S3 bucket and pass that to the kops CLI during cluster creation.

This post uses the bucket name kubernetes-aws-io. Bucket names must be unique; you have to use a different name. Create an S3 bucket:

aws s3api create-bucket --bucket kubernetes-aws-io

I strongly recommend versioning this bucket in case you ever need to revert or recover a previous version of the cluster. This can be enabled using the AWS CLI as well:

aws s3api put-bucket-versioning --bucket kubernetes-aws-io --versioning-configuration Status=Enabled

For convenience, you can also define KOPS_STATE_STORE environment variable pointing to the S3 bucket. For example:

export KOPS_STATE_STORE=s3://kubernetes-aws-io

This environment variable is then used by the kops CLI.

DNS configuration

As of Kops 1.6.1, a top-level domain or a subdomain is required to create the cluster. This domain allows the worker nodes to discover the master and the master to discover all the etcd servers. This is also needed for kubectl to be able to talk directly with the master.

This domain may be registered with AWS, in which case a Route 53 hosted zone is created for you. Alternatively, this domain may be at a different registrar. In this case, create a Route 53 hosted zone. Specify the name server (NS) records from the created zone as NS records with the domain registrar.

This post uses a kubernetes-aws.io domain registered at a third-party registrar.

Generate a Route 53 hosted zone using the AWS CLI. Download jq to run this command:

ID=$(uuidgen) && \
aws route53 create-hosted-zone \
--name cluster.kubernetes-aws.io \
--caller-reference $ID \
| jq .DelegationSet.NameServers

This shows an output such as the following:

[
"ns-94.awsdns-11.com",
"ns-1962.awsdns-53.co.uk",
"ns-838.awsdns-40.net",
"ns-1107.awsdns-10.org"
]

Create NS records for the domain with your registrar. Different options on how to configure DNS for the cluster are explained at github.com/kubernetes/kops/blob/master/docs/aws.md#configure-dns.

Experimental support to create a gossip-based cluster was added in Kops 1.6.2. This post uses a DNS-based approach, as that is more mature and well tested.

Create the Kubernetes cluster

The Kops CLI can be used to create a highly available cluster, with multiple master nodes spread across multiple Availability Zones. Workers can be spread across multiple zones as well. Some of the tasks that happen behind the scene during cluster creation are:

  • Provisioning EC2 instances
  • Setting up AWS resources such as networks, Auto Scaling groups, IAM users, and security groups
  • Installing Kubernetes.

Start the Kubernetes cluster using the following command:

kops create cluster \
--name cluster.kubernetes-aws.io \
--zones us-west-2a \
--state s3://kubernetes-aws-io \
--yes

In this command:

  • --zones
    Defines the zones in which the cluster is going to be created. Multiple comma-separated zones can be specified to span the cluster across multiple zones.
  • --name
    Defines the cluster’s name.
  • --state
    Points to the S3 bucket that is the state store.
  • --yes
    Immediately creates the cluster. Otherwise, only the cloud resources are created and the cluster needs to be started explicitly using the command kops update --yes. If the cluster needs to be edited, then the kops edit cluster command can be used.

This starts a single master and two worker node Kubernetes cluster. The master is in an Auto Scaling group and the worker nodes are in a separate group. By default, the master node is m3.medium and the worker node is t2.medium. Master and worker nodes are assigned separate IAM roles as well.

Wait for a few minutes for the cluster to be created. The cluster can be verified using the command kops validate cluster --state=s3://kubernetes-aws-io. It shows the following output:

Using cluster from kubectl context: cluster.kubernetes-aws.io

Validating cluster cluster.kubernetes-aws.io

INSTANCE GROUPS
NAME                 ROLE      MACHINETYPE    MIN    MAX    SUBNETS
master-us-west-2a    Master    m3.medium      1      1      us-west-2a
nodes                Node      t2.medium      2      2      us-west-2a

NODE STATUS
NAME                                           ROLE      READY
ip-172-20-38-133.us-west-2.compute.internal    node      True
ip-172-20-38-177.us-west-2.compute.internal    master    True
ip-172-20-46-33.us-west-2.compute.internal     node      True

Your cluster cluster.kubernetes-aws.io is ready

It shows the different instances started for the cluster, and their roles. If multiple cluster states are stored in the same bucket, then --name <NAME> can be used to specify the exact cluster name.

Check all nodes in the cluster using the command kubectl get nodes:

NAME                                          STATUS         AGE       VERSION
ip-172-20-38-133.us-west-2.compute.internal   Ready,node     14m       v1.6.2
ip-172-20-38-177.us-west-2.compute.internal   Ready,master   15m       v1.6.2
ip-172-20-46-33.us-west-2.compute.internal    Ready,node     14m       v1.6.2

Again, the internal IP address of each node, their current status (master or node), and uptime are shown. The key information here is the Kubernetes version for each node in the cluster, 1.6.2 in this case.

The kubectl value included in the PATH earlier is configured to manage this cluster. Resources such as pods, replica sets, and services can now be created in the usual way.

Some of the common options that can be used to override the default cluster creation are:

  • --kubernetes-version
    The version of Kubernetes cluster. The exact versions supported are defined at github.com/kubernetes/kops/blob/master/channels/stable.
  • --master-size and --node-size
    Define the instance of master and worker nodes.
  • --master-count and --node-count
    Define the number of master and worker nodes. By default, a master is created in each zone specified by --master-zones. Multiple master nodes can be created by a higher number using --master-count or specifying multiple Availability Zones in --master-zones.

A three-master and five-worker node cluster, with master nodes spread across different Availability Zones, can be created using the following command:

kops create cluster \
--name cluster2.kubernetes-aws.io \
--zones us-west-2a,us-west-2b,us-west-2c \
--node-count 5 \
--state s3://kubernetes-aws-io \
--yes

Both the clusters are sharing the same state store but have different names. This also requires you to create an additional Amazon Route 53 hosted zone for the name.

By default, the resources required for the cluster are directly created in the cloud. The --target option can be used to generate the AWS CloudFormation scripts instead. These scripts can then be used by the AWS CLI to create resources at your convenience.

Get a complete list of options for cluster creation with kops create cluster --help.

More details about the cluster can be seen using the command kubectl cluster-info:

Kubernetes master is running at https://api.cluster.kubernetes-aws.io
KubeDNS is running at https://api.cluster.kubernetes-aws.io/api/v1/proxy/namespaces/kube-system/services/kube-dns

To further debug and diagnose cluster problems, use 'kubectl cluster-info dump'.

Check the client and server version using the command kubectl version:

Client Version: version.Info{Major:"1", Minor:"6", GitVersion:"v1.6.4", GitCommit:"d6f433224538d4f9ca2f7ae19b252e6fcb66a3ae", GitTreeState:"clean", BuildDate:"2017-05-19T18:44:27Z", GoVersion:"go1.7.5", Compiler:"gc", Platform:"darwin/amd64"}
Server Version: version.Info{Major:"1", Minor:"6", GitVersion:"v1.6.2", GitCommit:"477efc3cbe6a7effca06bd1452fa356e2201e1ee", GitTreeState:"clean", BuildDate:"2017-04-19T20:22:08Z", GoVersion:"go1.7.5", Compiler:"gc", Platform:"linux/amd64"}

Both client and server version are 1.6 as shown by the Major and Minor attribute values.

Upgrade the Kubernetes cluster

Kops can be used to create a Kubernetes 1.4.x, 1.5.x, or an older version of the 1.6.x cluster using the --kubernetes-version option. The exact versions supported are defined at github.com/kubernetes/kops/blob/master/channels/stable.

Or, you may have used kops to create a cluster a while ago, and now want to upgrade to the latest recommended version of Kubernetes. Kops supports rolling cluster upgrades where the master and worker nodes are upgraded one by one.

As of kops 1.6.1, upgrading a cluster is a three-step process.

First, check and apply the latest recommended Kubernetes update.

kops upgrade cluster \
--name cluster2.kubernetes-aws.io \
--state s3://kubernetes-aws-io \
--yes

The --yes option immediately applies the changes. Not specifying the --yes option shows only the changes that are applied.

Second, update the state store to match the cluster state. This can be done using the following command:

kops update cluster \
--name cluster2.kubernetes-aws.io \
--state s3://kubernetes-aws-io \
--yes

Lastly, perform a rolling update for all cluster nodes using the kops rolling-update command:

kops rolling-update cluster \
--name cluster2.kubernetes-aws.io \
--state s3://kubernetes-aws-io \
--yes

Previewing the changes before updating the cluster can be done using the same command but without specifying the --yes option. This shows the following output:

NAME                 STATUS        NEEDUPDATE    READY    MIN    MAX    NODES
master-us-west-2a    NeedsUpdate   1             0        1      1      1
nodes                NeedsUpdate   2             0        2      2      2

Using --yes updates all nodes in the cluster, first master and then worker. There is a 5-minute delay between restarting master nodes, and a 2-minute delay between restarting nodes. These values can be altered using --master-interval and --node-interval options, respectively.

Only the worker nodes may be updated by using the --instance-group node option.

Delete the Kubernetes cluster

Typically, the Kubernetes cluster is a long-running cluster to serve your applications. After its purpose is served, you may delete it. It is important to delete the cluster using the kops command. This ensures that all resources created by the cluster are appropriately cleaned up.

The command to delete the Kubernetes cluster is:

kops delete cluster --state=s3://kubernetes-aws-io --yes

If multiple clusters have been created, then specify the cluster name as in the following command:

kops delete cluster cluster2.kubernetes-aws.io --state=s3://kubernetes-aws-io --yes

Conclusion

This post explained how to manage a Kubernetes cluster on AWS using kops. Kubernetes on AWS users provides a self-published list of companies using Kubernetes on AWS.

Try starting a cluster, create a few Kubernetes resources, and then tear it down. Kops on AWS provides a more comprehensive tutorial for setting up Kubernetes clusters. Kops docs are also helpful for understanding the details.

In addition, the Kops team hosts office hours to help you get started, from guiding you with your first pull request. You can always join the #kops channel on Kubernetes slack to ask questions. If nothing works, then file an issue at github.com/kubernetes/kops/issues.

Future posts in this series will explain other ways of creating and running a Kubernetes cluster on AWS.

— Arun