To Quiesce or Not to Quiesce Snapmirrors when upgrading ONTAP

[chrome kernel]

Upgrade Advisor from ONTAP 9.12.1 -> 9.13.1 or 9.14.1 does not list to pause/resume snapmirrors when doing OnTap upgrades. We run both Snapmirorr Async and Sync (not strict sync) relations across our storage clusters and previously we used to Quiesce these snapmirror relations prior to running ONTAP upgrades.

If we stop performing Snapmirror Quiesce before ONTAP upgrades, are there issues that we could encounter? Should we still pause/resume snapmirrors as we have done previously?

[pearl verge]

Not 100% sure. Usually I quiesce all SMs but sometimes I forget. But I can't remember having experienced any issues.
Make sure no transfers are actually running. I think ONTAP even checks this during validation and does not allow the update.

I see two scenarios:

• no SM-update is scheduled to run or is being triggered during your update --> No issues but you may get EMS-errors or error-messages in your backup-application if it triggers the update. But usually you would get the same errors if you quiesce the relationship because either way the backup-app can't trigger the replication to secondary so it will alarm you.
• SM-update happens during your update --> Should still be possible since the node which is not in takeover can handle the transfer (there's still a intercluster-LIF available). But I'm unsure if the automatic-giveback would be possible. I guess you would then have to wait until the transfer is finished (or abort it yourself) and then resume the update.

[wind tusk]

I confirmed today on a P1 that ONTAP stops SnapMirrors during a takeover.