#1 Global Leader in Data Resilience

Hyper-V VSS snapshot import delay

KB ID: 1844
Product: Veeam Backup & Replication
Version: 7.x
Published: 2013-12-18
Last Modified: 2020-08-13
mailbox
Get weekly article updates
By subscribing, you are agreeing to have your personal information managed in accordance with the terms of Veeam's Privacy Notice.
This site is protected by hCaptcha and its Privacy Policy and Terms of Service apply except as noted in our Privacy Policy.

Cheers for trusting us with the spot in your mailbox!

Now you’re less likely to miss what’s been brewing in our knowledge base with this weekly digest

error icon

Oops! Something went wrong.

Please, try again later.

Challenge

If you backup your VMs using Dell Equallogic hardware VSS provider in some cases data(vhd/vhdx) that we read from VSS snapshot could be inconsistent

Cause

During Hyper-V backup, we execute VSS API call DoSnapshotSet, as soon as it completes, we execute ImportSnapshot VSS API call, without any delay between two API calls.
Apparently Dell VSS hardware provider continues to write some data to VSS snapshot after execution of DoSnapshotSet method(after returning S_OK code), and if we try to immediately import VSS snapshot, we could backup inconsistent data from that VSS snapshot.

Solution

In order to workaround this problem we introduce a timeout/delay between execution of ImportSnapshot VSS API call
Open registry editor on Veeam Backup console
Navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Veeam\Veeam Backup and Replication
Create DWORD parameter:
HvDelayBeforeSnapshotImportCompleteSec
Set it to 90 seconds(or more if your hardware VSS provider requires more time).

To submit feedback regarding this article, please click this link: Send Article Feedback
To report a typo on this page, highlight the typo with your mouse and press CTRL + Enter.

Spelling error in text

This site is protected by hCaptcha and its Privacy Policy and Terms of Service apply except as noted in our Privacy Policy.
Thank you!

Thank you!

Your feedback has been received and will be reviewed.

Oops! Something went wrong.

Please, try again later.

You have selected too large block!

Please try select less.

KB Feedback/Suggestion

This form is only for KB Feedback/Suggestions, if you need help with the software open a support case

By submitting, you are agreeing to have your personal information managed in accordance with the terms of Veeam's Privacy Notice.
This site is protected by hCaptcha and its Privacy Policy and Terms of Service apply except as noted in our Privacy Policy.
Verify your email to continue your product download
We've sent a verification code to:
  • Incorrect verification code. Please try again.
An email with a verification code was just sent to
Didn't receive the code? Click to resend in sec
Didn't receive the code? Click to resend
Thank you!

Thank you!

Your feedback has been received and will be reviewed.

error icon

Oops! Something went wrong.

Please, try again later.