Description of problem: When we move a PV with a policy different from "Retain" the policy is changed to "Retain", and it remains like that in the destination cluster after the migration ends. Version-Release number of selected component (if applicable): MTC 1.4.0 How reproducible: Always Steps to Reproduce: 1. Deploy an application using an external nfs volume (that can be migrated) 2. Configure "Recycle" as the PV policy in the PVs used by this application oc edit pv ${PV_NAME} for instance oc get pv pv18 NAME CAPACITY ACCESS MODES RECLAIM POLICY STATUS CLAIM STORAGECLASS REASON AGE pv18 100Gi RWO,ROX,RWX Recycle Bound testmove2/nginx-html 26m 3. Migrate the application using "move" action to migrate the PV. Actual results: In the source and destination cluster the PV will be configured with "Retain" policy, instead of the original "Recycle". $ oc get pv pv18 NAME CAPACITY ACCESS MODES RECLAIM POLICY STATUS CLAIM STORAGECLASS REASON AGE pv18 100Gi RWO,ROX,RWX Retain Bound testmove2/nginx-html 31m Expected results: To configure the PV with "Retain" policy is necessary to avoid undesired behaviors while migrating the volume. Maybe the solution is not to restore the original policy, but to add some information in the MTC "move" action documentation explaining that this is a side effect of the "move" action, and that if we want the original policy back it should be done manually. Additional info: Be aware that restoring the original policy could lead to undesired interactions with rollback, and it needs to be handled carefully to avoid the volume data deletion, for instance, in case of "recycle".
What's not yet clear is what we want to do to fix this. There are a few options: 1) Do nothing; document this as a side effect of move operations 2) Annotate PVCs where we modify policy and restore the original policy post-restore. As mentioned in the bug, this has implications for rollback. It's possible that rollback will lose PV data if we do this and later attempt rollback. 3) Do the work from 2) above and also exclude these PVCs from rollback; document that "rollback" doesn't roll back moved PVs" 4) Annotate as on 2) but don't update policy. Provide some sort of post-migration action that will restore PVC policy once we no longer plan to do any more rollback operations. Document that once this is done, rollback is dangerous for moved PVs. Would this be a shell script or some other manual operation?
As discussed with John this morning, I think the right approach here is choice #4. We'll create an annotation for any PVC where we modify the policy, but we won't actually modify the policy post-migration. Reverting the policy post-migration brings with it the risk that rollback will delete user data. We don't want that, but we want to provide users with the information necessary to manually restore the pre-migration policy. To do this we want to add an annotation indicating the previous policy any time we modify policy as part of a migration action.
Fix is here: https://github.com/konveyor/openshift-velero-plugin/pull/67
Verified using MTC 1.4.0 openshift-migration-rhel7-operator@sha256:41d653c7fea749cb6add3aadb5716b9a443ab83adef88504915177bbc5aa0fda - name: MIG_CONTROLLER_REPO value: openshift-migration-controller-rhel8@sha256 - name: MIG_CONTROLLER_TAG value: 94b2886c52a97b39b6643cca5af7948a90be8a89f5110d596be117f34d54abff 2 PVCs were moved. One with Retain policy, the other one with Recycle policy. After the migration both pvcs had Retain policy. After the migration the pvc that originally had Recycle policy had this annotation: metadata: annotations: migration.openshift.io/orig-reclaim-policy: Recycle We need to take into account that if we execute a move migration and a rollback, the Recycle PV will have "Retain" policy after the rollback instead of the original one. It will have the annotation too. The rollback will not restore the original policy. Move to VERIFIED status.
Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory (Migration Toolkit for Containers (MTC) tool image release advisory 1.4.0), and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. https://access.redhat.com/errata/RHBA-2020:5329