Chapter 1. Migration from OpenShift Container Platform 3 to 4 overview

Before migrating from OpenShift Container Platform 3 to 4, you can check differences between OpenShift Container Platform 3 and 4. Review the following information:

Before migrating from OpenShift Container Platform 3 to 4, review the differences between OpenShift Container Platform 3 and 4 for information about the following areas:

You can migrate stateful application workloads from OpenShift Container Platform 3 to 4 at the granularity of a namespace. To learn more about MTC see Understanding MTC.

Review the following tasks to install the MTC:

You upgrade the Migration Toolkit for Containers (MTC) on OpenShift Container Platform 4.18 by using OLM. You upgrade MTC on OpenShift Container Platform 3 by reinstalling the legacy Migration Toolkit for Containers Operator.

Before you migrate your application workloads with the Migration Toolkit for Containers (MTC), review the premigration checklists.

You can migrate your applications by using the MTC web console or the command line.

You can automate your migrations and modify MTC custom resources to improve the performance of large-scale migrations by using the following options:

You can perform the following troubleshooting tasks:

You can roll back a migration by using the MTC web console, by using the CLI, or manually.

You can uninstall the MTC and delete its resources to clean up the cluster.