Backing up Windows 2016 Storage Replica VMs

[bhnelson]

Support case 04228432

How can I get AAP to work properly on a VM that's a Storage Replica source node? Currently, AAP (as well as vmware tools if I try that) tries to snapshot all volumes, including the Storage Replica log volume and fails. This is unsupported and documented here. I've confirmed that I can do a manual snapshot using diskshadow.exe with all volumes excluding the log volume and it is successful. Excluding the log volume in Veeam doesn't seem to affect what it tries to snapshot.

AAP for storage replica is listed in what's new for Veeam 9.5u4, but I can't find a scrap of documentation about it. We're on Veeam 10. I have two different replica sets and both seems to be behaving/failing in the same manner.

Thanks

[HannesK]

Hello,
the support for Windows Storage Replica is mentioned in the Veeam Agent for Windows section. Did you already try the VAW?

Best regards,
Hannes

PS: I added "Windows" to the topic title to avoid confusion with storage replica based on storage arrays

[bhnelson]

the support for Windows Storage Replica is mentioned in the Veeam Agent for Windows section [of the What's new guide]

Ah, you are correct. I did not notice that previously. I have not tried VAW yet in this case but I guess I might have to.

I still don't see any documentation whatsoever for this use. Is any special configuration needed for Storage Replica nodes? Just set them up with VAW, create a job, and... it works? I feel like they need to be set up in VAW like a failover cluster. But Storage Replica isn't a failover cluster so I don't see how that would be possible. How does it accomplish the "automatic exclusion of duplicate copies of data"?

To my original post: Is there a way to exclude a volume from the Veeam B&R VSS processing specifically? That would be a much simpler solution, granted without the duplicate data exclusion.

Thanks!

[HannesK]

and... it works?

yes. If not, please post the support case number.

I found such reg keys exist for SQL log exclusions. What about just disabling application aware processing? I cannot read about any application that would really require VSS.

Best regards,
Hannes

[Gostev]

vssadmin list writers command will show all applications with purpose-built VSS Writers. If you disable application-aware processing, the data for those applications will be exposed to potential loss. And as you go through the list, you will notice this includes even some core OS stuff like Windows Registry. Having said that, chances things will go wrong with crash-consistent backups are quite low.

[bhnelson]

Yes, per what Gostev said. I use AAP or quiescence (vmware snapshot) to guarantee a 'clean' backup. Maybe not absolutely necessary, but why wouldn't you if the functionality is there?

and... it works?

Well I can report that it does... work. The VAW AAP seems to properly exclude storage replica 'log' and 'target' volumes. Why the VBR AAP doesn't also do this is sadly puzzling, as I assume they come from the same code base. It doesn't seem there's any additional 'need' to use the agent in this case.

But while it works, I'm not sure it really does what I was expecting. Given the requirement for VAW, I assumed it would do some 'intelligent' management of the storage replica data, in the same was as backing up a failover cluster works. As mentioned in the release notes, "...including automatic exclusion of duplicate copies of data at backup time". In effect, it does do that by ignoring the target volume. But I strongly suspect if I failover the source and target node roles I would get a fresh full backup of the replica volume the next time veeam backup runs.

This is based on my observation of the backup jobs, and how their data is stored separately in the veeam repository. There doesn't appear to be any relationship in veeam between the source and target storage replica nodes. Maybe I'm wrong. I admittedly haven't tested it.

Thanks

[snorma01]

I am having this same issue, and in my case AAP is required for the VM that is running Storage Replica. This thread is over 2 years old, so I was wondering if there was now a recommended way to exclude a specific volume or disk from VSS snapshots that Veeam creates (without using VAW)? It seems like that should be possible.

[HannesK]

Hello,
and welcome to the forums.

Hmm, I remembered something from a different situation that might help... you could try VSS exclusions in Windows https://learn.microsoft.com/en-us/windo ... dow-copies

Best regards,
Hannes

[snorma01]

Hannes,

Thanks for the response. I have seen that Windows document and indeed a Windows solution prohibiting all applications from snapshotting that volume would be preferred in my case. However, it seems like that FilesNotToSnapshot registry entry has to be done for a specific application and not globally, i.e. Veeam would need to check a Veeam-specific key for it to work? Do you have more information on the exact procedure from the other situation you worked on?

Thanks,

Stephen

[snorma01]

As an update, I did try using the FilesNotToSnapshot registry key. Specifically, I added a REG_MULTI_SZ called VeeamExcludePaths with value L:\* /s (L: is the volume for the Storage Replica logs), but the server still hangs when running the Veeam job. I see that there is specific support for Storage Replica in Veeam agent for Windows, and it does work correctly if I use VAW backups, but changing these servers from VMware backups to VAW backups will have negative consequences like breaking our SureBackup jobs, so I'd like to get this working with VMware backups. Is there any way of getting the same Storage Replica support/behavior that is in VAW to work in VMware backups?

Or do you have more information about how I might get the registry key working for VMware backups? I saw in some other forums that people trying this before have seen that VSS still processes any read-only files even if they are excluded. That could explain why it didn't work for me but I'm not sure. If you have any advice for how I might get it working I would appreciate it.

Stephen

[HannesK]

Hello,
no, it was just an idea that might be worth to try because you said VAW is not an option (VAW stays the official recommendation).

What is meant with "breaking SureBackup jobs"? Sure Backup supports VAW since V12.

Best regards,
Hannes

[snorma01]

Oh interesting, we are on v11 but that might help to upgrade and try to mix the VAW and VMware machines in SureBackup. Do you know if there are any plans to add the same Storage Replica support to VMware backups as you have for VAW?

[HannesK]

Hello,
no plans so far. Two requests in three years with a workaround available...

Best regards,
Hannes