K8SPXC-1576: xtrabackup support poc

[mayankshah1607]

CHANGE DESCRIPTION

Support for backups using xtrabackup.

To enable this feature, set PXCO_FEATURE_GATES=BackupXtrabackup in the operator deployment.

CHECKLIST

Jira

• Is the Jira ticket created and referenced properly?
• Does the Jira ticket have the proper statuses for documentation (Needs Doc) and QA (Needs QA)?
• Does the Jira ticket link to the proper milestone (Fix Version field)?

Tests

• Is an E2E test/test case added for the new feature/change?
• Are unit tests added where appropriate?
• Are OpenShift compare files changed for E2E tests (compare/*-oc.yml)?

Config/Logging/Testability

• Are all needed new/changed options added to default YAML files?
• Are all needed new/changed options added to the Helm Chart?
• Did we add proper logging messages for operator actions?
• Did we ensure compatibility with the previous version or cluster upgrade process?
• Does the change support oldest and newest supported PXC version?
• Does the change support oldest and newest supported Kubernetes version?

[hors]

What about PVC backup? Will we support this type? In PXCO we have it.

[mayankshah1607]

hmm, I'm not sure we can support it. With SST, backup occurs on the job pod, so we create new PVC and mount it on the job and take backup there.

But now the architecture is different - the backup process occurs alongside pxc in a sidecar. So we cannot dynamically mount/unmount new PVC like we do in sst with a job. I'm not sure how we can implement PVC backups, we need to think about it maybe as a separate task. Maybe we can consider using VolumeSnapshots

[hors]

ok, we can do it via separate PR (not now)

[mayankshah1607]

One more trick I think we can try - since xtrabackup allows you to output a tar stream, we can stream that data from stdout to a grpc channel on another job. Then similar to our current approach, the job will mount the PVC and rebuild the backup data from the tar received over the stream.

To maintain consistency with s3 and azure, the job can similarly read xbstream from the grpc channel and run xbcloud there.

I think it is possible. Maybe we can use that approach in PS operator as well. Anyway, let's tackle it in a separate task.

[JNKPercona]

Test Name	Result	Time
auto-tuning-8-0	passed	00:18:37
allocator-8-0	passed	00:11:44
backup-storage-tls-8-0	passed	00:22:43
cross-site-8-0	passed	00:33:48
custom-users-8-0	passed	00:11:26
demand-backup-cloud-8-0	passed	00:56:04
demand-backup-encrypted-with-tls-8-0	passed	00:45:20
demand-backup-8-0	passed	00:42:44
demand-backup-flow-control-8-0	passed	00:10:15
demand-backup-parallel-8-0	passed	00:09:08
demand-backup-without-passwords-8-0	passed	00:15:24
haproxy-5-7	passed	00:14:19
haproxy-8-0	passed	00:14:27
init-deploy-5-7	passed	00:15:54
init-deploy-8-0	passed	00:16:42
limits-8-0	passed	00:11:59
monitoring-2-0-8-0	passed	00:22:13
monitoring-pmm3-8-0	passed	00:17:37
one-pod-5-7	passed	00:14:35
one-pod-8-0	passed	00:13:48
pitr-8-0	passed	00:43:20
pitr-gap-errors-8-0	passed	00:54:57
proxy-protocol-8-0	passed	00:09:08
proxy-switch-8-0	passed	00:13:26
proxysql-sidecar-res-limits-8-0	passed	00:08:30
proxysql-scheduler-8-0	passed	00:16:05
pvc-resize-5-7	passed	00:14:32
pvc-resize-8-0	passed	00:16:45
recreate-8-0	passed	00:16:51
restore-to-encrypted-cluster-8-0	passed	00:25:32
scaling-proxysql-8-0	passed	00:08:17
scaling-8-0	passed	00:10:30
scheduled-backup-5-7	passed	01:05:26
scheduled-backup-8-0	passed	01:02:37
security-context-8-0	passed	00:25:22
smart-update1-8-0	passed	00:32:32
smart-update2-8-0	passed	00:37:15
storage-8-0	failure	00:42:45
tls-issue-cert-manager-ref-8-0	passed	00:08:29
tls-issue-cert-manager-8-0	passed	00:09:44
tls-issue-self-8-0	passed	00:13:16
upgrade-consistency-8-0	passed	00:22:51
upgrade-haproxy-5-7	passed	00:23:59
upgrade-haproxy-8-0	passed	00:23:48
upgrade-proxysql-5-7	passed	00:13:37
upgrade-proxysql-8-0	passed	00:14:22
users-5-7	passed	00:25:19
users-8-0	passed	00:24:46
validation-hook-8-0	passed	00:01:47

Summary	Value
Tests Run	49/49
Job Duration	02:48:16
Total Test Time	18:25:00

commit: 91588dd
image: perconalab/percona-xtradb-cluster-operator:PR-2274-91588dd2