Embedded Cluster platform

Replicated Embedded Cluster allows you to distribute a Kubernetes cluster and your application together as a single appliance, making it easy for enterprise users to install, update, and manage the application and the cluster in tandem. Embedded Cluster is based on the open source Kubernetes distribution k0s. For more information, see the k0s documentation.

In Embedded Cluster, all components and functionalities are consolidated into a single binary, this binary facilitates a streamlined cluster installation process, removing the need for external dependencies (rpms, debs, etc).

Embedded Cluster includes by default the Kots Admin Console, the OpenEBS Storage provisioner, and Velero for backups and disaster recovery. Additionally, it includes a Registry when deployed in air gap mode.

Development

Requirements

• MacOS
• Docker Desktop with sufficient resources allocated:
  • Open Docker Desktop -> Settings -> Resources
  • Increase allocated resources as needed. Higher allocations will significantly enhance the development environment speed and responsiveness.
• Replicated CLI
• Helm CLI
• AWS CLI
• jq
• Dagger

Running the Development Environment

1. Clone the Embedded Cluster repo:

   git clone https://github.com/replicatedhq/embedded-cluster.git
   cd embedded-cluster

2. Set the following environment variables:

   export REPLICATED_APP=
   export REPLICATED_API_TOKEN=
   export REPLICATED_API_ORIGIN=
   export APP_CHANNEL=
   export APP_CHANNEL_ID=
   export APP_CHANNEL_SLUG=
   export AWS_ACCESS_KEY_ID=
   export AWS_SECRET_ACCESS_KEY=

   Environment Variable	Description	Default Value
   REPLICATED_APP	The application slug	embedded-cluster-smoke-test-staging-app
   REPLICATED_API_TOKEN	A vendor portal API token with write access to the application	(required)
   REPLICATED_API_ORIGIN	The vendor-api URL	https://api.staging.replicated.com/vendor
   APP_CHANNEL	The channel name (it's recommended to create a new channel just for your development environment.)	(required)
   APP_CHANNEL_ID	The channel ID	(required)
   APP_CHANNEL_SLUG	The channel slug	(required)
   AWS_ACCESS_KEY_ID	AWS access key ID with write access to the dev-embedded-cluster-bin bucket in Replicated's dev AWS account	(required)
   AWS_SECRET_ACCESS_KEY	AWS secret access key with write access to the dev-embedded-cluster-bin bucket in Replicated's dev AWS account	(required)

   Note:

   • To use a different AWS bucket or account, override using the S3_BUCKET environment variable.
   • To use the Replicated staging bucket used in CI, set USES_DEV_BUCKET=0.

3. Create a release for initial installation:

   make initial-release

   This step creates a release that is intended to be used for initial installation, not for upgrades. It creates a release of the application using the manifests located in the e2e/kots-release-install directory. It may take a few minutes to complete the first time as nothing is cached yet.

4. Create the first node:

   make create-node0

   This command sets up the initial node for your cluster and SSHs into it.

   By default, a Debian-based node will be created. If you want to use a different distribution, you can set the DISTRO environment variable:

   make create-node0 DISTRO=almalinux-8

   To view the list of available distributions:

   make list-distros

5. In the Vendor Portal, create and download a license that is assigned to the channel. We recommend storing this license in the local-dev/ directory, as it is gitignored and not otherwise used by the CI.

6. Install Embedded Cluster:

   output/bin/embedded-cluster install --license <license-file>

7. Once that completes, you can access the admin console at http://localhost:30000

Interacting with the cluster

You can interact with the cluster using kubectl by running the following command:

output/bin/embedded-cluster shell

This will drop you in a new shell, this shell is configured to reach the cluster and includes shell completion. Example output:

$ output/bin/embedded-cluster shell

    __4___
 _  \ \ \ \   Welcome to embedded-cluster-smoke-test-staging-app debug shell.
<'\ /_/_/_/   This terminal is now configured to access your cluster.
 ((____!___/) Type 'exit' (or CTRL+d) to exit.
  \0\0\0\0\/  Happy hacking.
 ~~~~~~~~~~~
$ export KUBECONFIG="/var/lib/k0s/pki/admin.conf"
$ export PATH="$PATH:/var/lib/embedded-cluster/bin"
$ source <(kubectl completion bash)
$ source /etc/bash_completion
$ 

Creating an upgrade release

To create an upgrade release, run the following command:

make upgrade-release

This step creates a release that is intended to be used for upgrades. It creates a release of the application using the manifests located in the e2e/kots-release-upgrade directory. The release will show up in the KOTS admin console as an available update.

Creating additional nodes

To create additional nodes, run the following command:

make create-node<node-number>

For example:

make create-node1

These additional nodes can either be joined to your existing Embedded Cluster installation, or used to set up separate, independent Embedded Cluster instances.

Deleting nodes

If the node is part of a multi-node Embedded Cluster installation, it's recommended to remove it from the cluster first by running the following commands:

make ssh-node<node-number>

output/bin/embedded-cluster reset

To delete a node, run the following command:

make delete-node<node-number>

For example:

make delete-node1

Establishing SSH sessions

To SSH into an existing node, run the following command:

make ssh-node<node-number>

For example:

make ssh-node0

Developing Embedded Cluster Operator

1. To apply your current changes, run the following commands:

   make operator-up

   make build run

2. To apply additional changes, stop the current process with Ctrl+C, then run the following command:

   make build run

3. When finished developing, run the following commands to revert back to the original state:

   exit

   make operator-down

Developing KOTS components

1. Clone the KOTS repo to the same parent directory as Embedded Cluster:

   cd ..
   git clone https://github.com/replicatedhq/kots.git
   cd kots

2. When developing KOTS components, the connection is made to node0 by default. To connect to a KOTS instance on a different node, set the EC_NODE environment variable to the name of that node:

   export EC_NODE=node1

Developing kotsadm web / API

1. To apply your current changes, run the following commands:

   make kotsadm-up-ec

   make build run

   Subsequent changes to the kotsadm web component are reflected in real-time, no manual steps required.

2. To apply additional API changes, stop the current process with Ctrl+C, then run the following command:

   make build run

3. When finished developing, run the following commands to revert back to the original state:

   exit

   make kotsadm-down-ec

Developing kurl-proxy web / API

1. To apply your current changes, run the following commands:

   make kurl-proxy-up-ec

   make build run

2. To apply additional changes, stop the current process with Ctrl+C, then run the following command:

   make build run

3. When finished developing, run the following commands to revert back to the original state:

   exit

   make kurl-proxy-down-ec