IBM Power Systems adds official support for Limited Live Migration from OpenShiftSDN to OVN-Kubernetes. Administrators are able to migrate off OpenShiftSDN cluster networks to OVN-Kubernetes without experiencing service interruption. As the preferred migration path, it ensures that enterprise workloads running on OpenShift COntainer Platform on IBM Power maintain continuous availability. For environments where a live transition is not feasible, IBM Power also supports the offline migration method to ensure a successful network evolution.
Steps
- Verifying Setup a. Ensure you are the latest
eus-4.16which is4.16.54. We used this when testing. OpenShift Upgrade Path b. Ensure theoc get coreturns all Operators Ready and none are degrated. c. Review Diagnostic Steps in the Knowledge Base Article: Limited Live Migration from OpenShift SDN to OVN-Kubernetes https://access.redhat.com/solutions/7057169 - If everything is OK, you can initiate the limited live migration per 19.5.1.5.4. Initiating the limited live migration process
oc patch Network.config.openshift.io cluster --type='merge' --patch '{"metadata":{"annotations":{"network.openshift.io/network-type-migration":""}},"spec":{"networkType":"OVNKubernetes"}}'
- Watch the
network.configto see it is complete.
oc patch Network.config.openshift.io cluster --type='merge' --patch '{"metadata":{"annotations":{"network.openshift.io/network-type-migration":""}},"spec":{"networkType":"OVNKubernetes"}}'
- After a successful migration operation, remove the
network.openshift.io/network-type-migration-annotation from thenetwork.configcustom resource by entering the following command:
oc annotate network.config cluster network.openshift.io/network-type-migration-
- Afterwards, you may see the following output in
network.config, this is OK, and expected.
# oc get network.config -oyaml
apiVersion: config.openshift.io/v1
kind: Network
metadata:
creationTimestamp: "2025-12-09T07:03:09Z"
generation: 18
name: cluster
resourceVersion: "545748"
uid: b3ec83d9-f1ba-4a44-959a-0c60f3e19866
spec:
clusterNetwork:
- cidr: 10.128.0.0/14
hostPrefix: 23
externalIP:
policy: {}
networkType: OVNKubernetes
serviceNetwork:
- 172.30.0.0/16
status:
clusterNetwork:
- cidr: 10.128.0.0/14
hostPrefix: 23
clusterNetworkMTU: 1350
conditions:
- lastTransitionTime: "2025-12-10T07:25:55Z"
message: ""
reason: AsExpected
status: "True"
type: NetworkDiagnosticsAvailable
- lastTransitionTime: "2025-12-10T07:41:38Z"
message: Network type migration is not in progress
reason: NetworkTypeMigrationNotInProgress
status: Unknown
type: NetworkTypeMigrationMTUReady
- lastTransitionTime: "2025-12-10T07:41:38Z"
message: Network type migration is not in progress
reason: NetworkTypeMigrationNotInProgress
status: Unknown
type: NetworkTypeMigrationTargetCNIAvailable
- lastTransitionTime: "2025-12-10T07:41:38Z"
message: Network type migration is not in progress
reason: NetworkTypeMigrationNotInProgress
status: Unknown
type: NetworkTypeMigrationTargetCNIInUse
- lastTransitionTime: "2025-12-10T07:41:38Z"
message: Network type migration is not in progress
reason: NetworkTypeMigrationNotInProgress
status: Unknown
type: NetworkTypeMigrationOriginalCNIPurged
- lastTransitionTime: "2025-12-10T07:41:38Z"
message: Network type migration is completed
reason: NetworkTypeMigrationCompleted
status: "False"
type: NetworkTypeMigrationInProgress
networkType: OVNKubernetes
serviceNetwork:
- 172.30.0.0/16
Best wishes with your migration.
Reference
19.5.1.1. Supported platforms when using the limited live migration methodhttps://docs.redhat.com/en/documentation/openshift_container_platform/4.16/html/networking/ovn-kubernetes-network-plugin#supported-platforms-live-migrating-ovn-kubernetes
