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Hi
We have a scheduled maintenance window which allows downtime and want to patch all the VMs concurrently. We have configured Dynamic Scope and Schedules in the Azure Update Manager. The problem is that we have more than 1 VM and they all belong to the same Availability Set.
Is there any way, other than having multiple schedules or extending the schedule (we can't have more than 2 hours), to allow for all the VMs to patch simultaneously in an AV Set? At the moment, it can only patch one or two VMs and skips the remaining because there is not enough time left. We can afford to have all the VMs to go offline at the same time.
Hi, Unfortunately there is not other way besides configuring multiple schedules so the VMs patch at different time.
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Hi, sorry after reading a bit more about Update Domains in AVSet, looks like that all the 6 VMs (as per the picture above) should've been updated concurrently because they are in the same UD, as per the documentation. But this didn't happen and the second VM patching wasn't started until first one finished.
The other documentation however says "All VMs in a common availability set aren't updated concurrently" which seems contradicting the above statement.
Does this mean that the multiple VMs in the same AVSet can't be patched concurrently, regardless of how many Update Domains there are in that AVSet?
Can you please clarify?
When we talk about VMs in availability sets patched by Azure Update Manager the statement in Azure Update Manager documentation is correct one.
"In scenarios where machines from the same availability set are being patched at the same time in different schedules, it is likely that they might not get patched or could potentially fail if the maintenance window exceeds. To avoid this, we recommend that you either increase the maintenance window or split the machines belonging to the same availability set across multiple schedules at different times."