Premigration checklists

    • The cluster meets the minimum hardware requirements.

    • You have installed the correct legacy Migration Toolkit for Containers Operator version:

      • on OKD version 3.7.

      • operator.yml on OKD versions 3.9 to 4.5.

    • All nodes have an active OKD subscription.

    • All the have been performed.

    • All the environment health checks have been performed.

    • You have checked for persistent volumes (PVs) with abnormal configurations stuck in a Terminating state by running the following command:

    • You have checked for pods with a high restart count by running the following command:

      Even if the pods are in a Running state, a high restart count might indicate underlying problems.

    • The internal registry uses a .

    • Direct image migration only: The internal registry is exposed to external traffic.

    • You can read and write images to the registry.

    • The is healthy.

    • The average API server response time on the source cluster is less than 50 ms.

    • The cluster certificates are for the duration of the migration process.

    • You have checked for pending certificate-signing requests by running the following command:

    • The identity provider is working.

    • You have installed Migration Toolkit for Containers Operator version 1.5.1.

    • The cluster meets the minimum hardware requirements for the specific platform and installation method, for example, on .

    • The cluster has the correct network configuration and permissions to access external services, for example, databases, source code repositories, container image registries, and CI/CD tools.

    • External applications and services that use services provided by the cluster have the correct network configuration and permissions to access the cluster.

    • Internal container image dependencies are met.

      If an application uses an internal image in the namespace that is not supported by OKD 4.7, you can manually update the OKD 3 image stream tag with podman.

    • The target cluster and the replication repository have sufficient storage space.

    • The is working.

    • Set the value of the parameter to true for each OKD route to update its host name for the target cluster. Otherwise, the migrated routes retain the source cluster host name.

    • The migration network has a minimum throughput of 10 Gbps.

    • The clusters have sufficient resources for migration.

      Clusters require additional memory, CPUs, and storage in order to run a migration on top of normal workloads. Actual resource requirements depend on the number of Kubernetes resources being migrated in a single migration plan. You must test migrations in a non-production environment in order to estimate the resource requirements.