The release notes for Migration Toolkit for Containers (MTC) describe new features and enhancements, deprecated features, and known issues.
The MTC enables you to migrate application workloads between OpenShift Container Platform clusters at the granularity of a namespace.
You can migrate from OpenShift Container Platform 3 to 4.16 and between OpenShift Container Platform 4 clusters.
MTC provides a web console and an API, based on Kubernetes custom resources, to help you control the migration and minimize application downtime.
For information on the support policy for MTC, see OpenShift Application and Cluster Migration Solutions, part of the Red Hat OpenShift Container Platform Life Cycle Policy.
This release has the following new features and enhancements:
State migration: You can perform repeatable, state-only migrations by selecting specific persistent volume claims (PVCs).
"New operator version available" notification: The Clusters page of the MTC web console displays a notification when a new Migration Toolkit for Containers Operator is available.
This release has the following known issues:
On OpenShift Container Platform 3.10, the MigrationController
pod takes too long to restart. The Bugzilla report contains a workaround. (BZ#1986796)
Stage
pods fail during direct volume migration from a classic OpenShift Container Platform source cluster on IBM Cloud. The IBM block storage plugin does not allow the same volume to be mounted on multiple pods of the same node. As a result, the PVCs cannot be mounted on the Rsync pods and on the application pods simultaneously. To resolve this issue, stop the application pods before migration. (BZ#1887526)
MigPlan
custom resource does not display a warning when an AWS gp2 PVC has no available space. (BZ#1963927)
Block storage for IBM Cloud must be in the same availability zone. See the IBM FAQ for block storage for virtual private cloud.