Merge branch 'selhorn-more-migration-details' into 'master'

Added more details about the deprecation

See merge request gitlab-org/gitlab!80961

doc/user/infrastructure/clusters/migrate_to_gitlab_agent.md

@@ -4,85 +4,78 @@ group: Configure
 info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#assignments
 ---
 
-# Migrate to the GitLab Agent for Kubernetes **(FREE)**
+# Migrate to the GitLab agent for Kubernetes **(FREE)**
 
-The first integration between GitLab and Kubernetes used cluster certificates
-to connect the cluster to GitLab.
-This method was [deprecated](https://about.gitlab.com/blog/2021/11/15/deprecating-the-cert-based-kubernetes-integration/)
-in GitLab 14.5 in favor of the [GitLab Agent for Kubernetes](../../clusters/agent/index.md).
+To connect your Kubernetes cluster with GitLab, you can use:
 
-To make sure your clusters connected to GitLab do not break in the future,
-we recommend you migrate to the GitLab Agent as soon as possible by following
-the processes described in this document.
+- [A GitOps workflow](../../clusters/agent/gitops.md).
+- [A GitLab CI/CD workflow](../../clusters/agent/ci_cd_tunnel.md).
+- [A certificate-based integration](index.md).
 
-The certificate-based integration was used for some popular GitLab features such as,
-GitLab Managed Apps, GitLab-managed clusters, and Auto DevOps.
+The certificate-based integration is
+[**deprecated**](https://about.gitlab.com/blog/2021/11/15/deprecating-the-cert-based-kubernetes-integration/)
+in GitLab 14.5. It is expected to be
+[turned off by default in 15.0](../../../update/deprecations.md#certificate-based-integration-with-kubernetes)
+and removed in GitLab 15.6.
+
+If you are using the certificate-based integration, you should move to another workflow as soon as possible. 
 
-As a general rule, migrating clusters that rely on GitLab CI/CD can be
-achieved using the [CI/CD Tunnel](../../clusters/agent/ci_cd_tunnel.md)
-provided by the Agent.
+As a general rule, to migrate clusters that rely on GitLab CI/CD,
+you can use the [CI/CD workflow](../../clusters/agent/ci_cd_tunnel.md).
+This workflow uses an agent to connect to your cluster. The agent:
+
+- Is not exposed to the internet.
+- Does not require full cluster-admin access to GitLab.
 
 NOTE:
-The GitLab Agent for Kubernetes does not intend to provide feature parity with the
-certificate-based cluster integrations. As a result, the Agent doesn't support
-all the features available to clusters connected through certificates.
+The certificate-based integration was used for popular GitLab features like
+GitLab Managed Apps, GitLab-managed clusters, and Auto DevOps.
+Some features are currently available only when using certificate-based integration.
 
 ## Migrate cluster application deployments
 
 ### Migrate from GitLab-managed clusters
 
 With GitLab-managed clusters, GitLab creates separate service accounts and namespaces
-for every branch and deploys using these resources.
+for every branch and deploys by using these resources.
 
-To achieve a similar result with the GitLab Agent, you can use [impersonation](../../clusters/agent/ci_cd_tunnel.md#use-impersonation-to-restrict-project-and-group-access)
+The GitLab agent uses [impersonation](../../clusters/agent/ci_cd_tunnel.md#use-impersonation-to-restrict-project-and-group-access)
 strategies to deploy to your cluster with restricted account access. To do so:
 
 1. Choose the impersonation strategy that suits your needs.
 1. Use Kubernetes RBAC rules to manage impersonated account permissions in Kubernetes.
-1. Use the `access_as` attribute in your Agent’s configuration file to define the impersonation.
+1. Use the `access_as` attribute in your agent configuration file to define the impersonation.
 
 ### Migrate from Auto DevOps
 
-To configure your Auto DevOps project to use the GitLab Agent:
+To configure your Auto DevOps project to use the GitLab agent:
 
-1. Follow the steps to [install an agent](../../clusters/agent/install/index.md) on your cluster.
-1. Go to the project in which you use Auto DevOps.
-1. From the sidebar, select **Settings > CI/CD** and expand **Variables**.
+1. Follow the steps to [install an agent](../../clusters/agent/install/index.md) in your cluster.
+1. Go to the project where you use Auto DevOps.
+1. On the left sidebar, select **Settings > CI/CD** and expand **Variables**.
 1. Select **Add new variable**.
 1. Add `KUBE_CONTEXT` as the key, `path/to/agent/project:agent-name` as the value, and select the environment scope of your choice.
 1. Select **Add variable**.
 1. Repeat the process to add another variable, `KUBE_NAMESPACE`, setting the value for the Kubernetes namespace you want your deployments to target, and set the same environment scope from the previous step.
-1. From the sidebar, select **Infrastructure > Kubernetes clusters**.
+1. On the left sidebar, select **Infrastructure > Kubernetes clusters**.
 1. From the certificate-based clusters section, open the cluster that serves the same environment scope.
 1. Select the **Details** tab and disable the cluster.
-1. To activate the changes, from the project's sidebar, select **CI/CD > Variables > Run pipeline**.
+1. To activate the changes, on the left sidebar, select **CI/CD > Variables > Run pipeline**.
 
-### Migrate generic deployments
-
-When you use Kubernetes contexts to reach the cluster from GitLab, you can use the [CI/CD Tunnel](../../clusters/agent/ci_cd_tunnel.md)
-directly. It injects the available contexts into your CI environment automatically:
+For an example, [view this project](https://gitlab.com/gitlab-examples/ops/gitops-demo/hello-world-service).
 
-1. Follow the steps to [install an agent](../../clusters/agent/install/index.md) on your cluster.
-1. Go to the project in which you use Auto DevOps.
-1. From the sidebar, select **Settings > CI/CD** and expand **Variables**.
-1. Select **Add new variable**.
-1. Add `KUBE_CONTEXT` as the key, `path/to/agent-configuration-project:your-agent-name` as the value, and select the environment scope of your choice.
-1. Edit your `.gitlab-ci.yml` file and set the Kubernetes context to the `KUBE_CONTEXT` you defined in the previous step:
+### Migrate generic deployments
 
-   ```yaml
-   <your job name>:
-     script:
-     - kubectl config use-context $KUBE_CONTEXT
-   ```
+Follow the process for the [CI/CD workflow](../../clusters/agent/ci_cd_tunnel.md).
 
-## Migrate from GitLab Managed Applications
+## Migrate from GitLab Managed applications
 
-Follow the process to [migrate from GitLab Managed Apps to the Cluster Management Project](../../clusters/migrating_from_gma_to_project_template.md).
+Follow the process to [migrate from GitLab Managed Apps to the cluster management project](../../clusters/migrating_from_gma_to_project_template.md).
 
-## Migrating a Cluster Management project
+## Migrate a cluster management project
 
-See [how to use a cluster management project with the GitLab Agent](../../clusters/management_project_template.md#use-the-agent-with-the-cluster-management-project-template).
+See [how to use a cluster management project with the GitLab agent](../../clusters/management_project_template.md#use-the-agent-with-the-cluster-management-project-template).
 
 ## Migrate cluster monitoring features
 
-Cluster monitoring features are not supported by the GitLab Agent for Kubernetes yet.
+Cluster monitoring features are not yet supported by the GitLab agent for Kubernetes.