Failed to prepare guests for volume snapshot

[Trkkr]

- I am getting this error on a new install of Veeam 7.0.
- This is a Windows 2008 R2 x64 host running 2 Windows 2008 R2 x64 Hyper-V servers.
- My repository is a NAS on the network.
- I have created a backup job to backup one of the VMs to the NAS. Running the backup this message pops up 30 seconds into the job, right after the line 'Preparing next VM for processing'

Anyone know how to fix this? Thanks.

[foggy]

Please open a case with technical support as it is advised to do with all technical issues when you click New Topic. Job logs will show the exact reason of the failure. This could be a VSS writer failure, for example, so running 'vssadmin list writers' command on the guest server could give some thoughts.

[mrenbe]

Hello,

I have the same issue.
Did you finally found a solution to this issue?

Thx

[foggy]

Michael, did you run the 'vssadmin list writers' command on the guest? Have you already contacted support? The OP hasn't provided his case number and I cannot check it for solution, so opening your own case is recommended.

[mrenbe]

Yes I've checked the writers on the Guest VM.

Code: Select all

PS C:\Windows\system32> vssadmin list writers
vssadmin 1.1 - Volume Shadow Copy Service administrative command-line tool
(C) Copyright 2001-2005 Microsoft Corp.

Writer name: 'Task Scheduler Writer'
   Writer Id: {d61d61c8-d73a-4eee-8cdd-f6f9786b7124}
   Writer Instance Id: {1bddd48e-5052-49db-9b07-b96f96727e6b}
   State: [1] Stable
   Last error: No error

Writer name: 'VSS Metadata Store Writer'
   Writer Id: {75dfb225-e2e4-4d39-9ac9-ffaff65ddf06}
   Writer Instance Id: {088e7a7d-09a8-4cc6-a609-ad90e75ddc93}
   State: [1] Stable
   Last error: No error

Writer name: 'Performance Counters Writer'
   Writer Id: {0bada1de-01a9-4625-8278-69e735f39dd2}
   Writer Instance Id: {f0086dda-9efc-47c5-8eb6-a944c3d09381}
   State: [1] Stable
   Last error: No error

Writer name: 'System Writer'
   Writer Id: {e8132975-6f93-4464-a53e-1050253ae220}
   Writer Instance Id: {d310dcca-5da0-489a-8fb3-d2f1198ebbf4}
   State: [1] Stable
   Last error: No error

Writer name: 'ASR Writer'
   Writer Id: {be000cbe-11fe-4426-9c58-531aa6355fc4}
   Writer Instance Id: {f7f1dd52-db80-4644-94d2-e64c460f4918}
   State: [1] Stable
   Last error: No error

Writer name: 'SqlServerWriter'
   Writer Id: {a65faa63-5ea8-4ebc-9dbd-a0c4db26912a}
   Writer Instance Id: {c66e84f8-862c-407b-9c70-1bc443237d18}
   State: [1] Stable
   Last error: No error

Writer name: 'Shadow Copy Optimization Writer'
   Writer Id: {4dc3bdd4-ab48-4d07-adb0-3bee2926fd7f}
   Writer Instance Id: {1b44f60f-8116-4ac2-a0c5-032131921ba5}
   State: [1] Stable
   Last error: No error

Writer name: 'COM+ REGDB Writer'
   Writer Id: {542da469-d3e1-473c-9f4f-7847f01fc64f}
   Writer Instance Id: {b08b9693-0b5f-41b7-9fd6-60b37045600f}
   State: [1] Stable
   Last error: No error

Writer name: 'Registry Writer'
   Writer Id: {afbab4a2-367d-4d15-a586-71dbb18f8485}
   Writer Instance Id: {29daece6-603b-4d1d-96ae-885a5be162ff}
   State: [1] Stable
   Last error: No error

Writer name: 'WMI Writer'
   Writer Id: {a6ad56c2-b509-4e6c-bb19-49d8f43532f0}
   Writer Instance Id: {be1b375a-ad40-4ed4-8a79-430f4e9bd081}
   State: [1] Stable
   Last error: No error

This is for Windows 2008R2 SP1 VM running on Hyper-V on Windows 2008R2SP1 (FailoverClusters & CSV). I take snapshots simulteaneously with Equallogic ASM.
The log on the host indicates that it is tryning to take a backup in Saved State however my VM is online and running. I use Veeam 8 with a trial waiting my futur license (today or maybe tomorrow).

Michael

[foggy]

Probably, online backup is not possible for some reason. Anyway, please contact technical support directly for further investigation.

[Vitaliy S.]

I take snapshots simulteaneously with Equallogic ASM.

Do you take these snapshots on the volume level or guest OS?

[Trkkr]

Hi All,

Been quite awhile but I started running into the same issue again and saw this post from myself a few years back! I did get a hold of Veeam Support and they had me send log files to them. They came back saying the logs were showing 'Unknown username or bad password' and had me update the Guest Processing credentials.

Since this post came up as one of the top results on Google I figured I should update this ticket with the results from 2013 as well as whatever happens to be the issue this time as I don't believe Guest Processing Credentials is the cause (those haven't changed since the last successful backup). I switched out the NAS and upgraded from v8x to v9 Update 1. I should've seen if the backups would run before upgrading but hindsight is always 20-20. I will contact Veeam again and see what the issue is now.

[wael.nady]

Trkkr, i see the same error in couple of locations , don't believe Guest Processing Credentials is the cause as well since it was working before and some times few VMs fails in the same backup task while other VM success
in most cases the backup repository is a local drive, no NAS included
i'm wondering where you can find the error 'Unknown username or bad password' as there is a test now button to make sure that credentials are vaild

[Trkkr]

Hi Wael,

I did run that check and it was successful. However, on a related note, I have found the cause of this issue this time.

The error only came up when 'Application Aware Processing' was enabled. In discussions with Veeam Support they said that AAP needs to be enabled for any Domain Controllers or database servers (which one of our problems servers works as both). A bit of digging around with Veeam and they directed me a particular error message in Event Viewer: Under 'Application and Services Logs\Microsoft\Windows\Hyper-V-Integration\Admin' there were a string of errors, for both of our VMs: "'[VM Name]': The Volume Shadow Copy integration service is either not enabled, not running, or not initialized...."

Veeam Support was unable to assist with fixing this error. A bit more digging on our own we found the solution:
- In Hyper-V Manager, in the Settings window for the VM, under the 'Management' section, there is an 'Integration Services' option. Under there you can check/un-check different items. One of those items is 'Backup (volume snapshot)'. Not sure why that was un-checked but checking it off and running the backup with AAP enabled runs successfully.

As I mentioned, the only thing that was changed manually by 'us' was the upgrade of Veeam from v8 to v9 and a new NAS. I'm not sure what caused that option to become unchecked but it's something to check if you're running into the same issue.

[Brunok]

Hi all,
we have a Hyper-V 2012 R2 Host, with one virtual machine running veeam.

When backing up the virtual machines (Windows 2012 R2 Servers), we've getting following errors during the first attempt when Veeam starts:

VSS processing cannot be performed due to unknown guest OS type
Failed to create snapshot (Microsoft Software Shadow Copy provider 1.0) (mode: Veeam application-aware processing) Details: Failed to prepare guests for volume snapshot.
Failed to create snapshot (Microsoft Software Shadow Copy provider 1.0) (mode: Veeam application-aware processing) Details: Failed to prepare guests for volume snapshot.
Error: Failed to prepare guests for volume snapshot.

few minutes later, the server backup works ok.

I've read the article https://www.veeam.com/de/kb1855 and everything is ok, according this article.

Strange thing: when the Hyper-V Host is rebooted - the first complete Backup-Job after the reboot works without any problem. The next days, the backup shows the errors again...

Thanks for helping
Bruno

[Shestakov]

Hi Bruno!
Do you use Veeam ONE? There is a configuration assessment report which checks VSS requestor, Integration Services and other misconfigurations.
I would also contact Veeam support as issue looks really strange.
Thanks!

[Brunok]

Thanks, just installed Veeam One. The Hyper-V VSS Requestor state shows warnings.
SERVER Running / Manual Warning

I changed the Hyper-V Services from manual to automatic now, but the report seem not to refresh the state (even after a reboot and clear the IE cache). Does it take some time until the state change in the report ?

Bruno

[Shestakov]

Yes it does.
You may also refresh data manually in Veeam ONE Reporter > Configuration > Servers and click "Run now" button.

[Brunok]

Hello,
i need to open this thread again. Still errors in processing the backups. After a reboot of the Hyper-V Server with all virtual machines the backup runs without any problem. But the following backups (the other days) has errors, after 3 or more retries the are ok. The configuration report shows "warnings", even if i change the service from "manual" to "Auto"



Any ideas ?

Thanks
Bruno

[Shestakov]

Hello Bruno,
Warning is shown as a reminder for you set the automatic start of the service. If it`s running though, despite how it was started, it should cause any troubles.
I would suggest you to contact the support team for the issue investigation.
Thanks!