Problem
- a backup cannot be verified (where verify option enabled in backup schedule or attempted using Verify Images page)
- errors encountered when trying to recover from backups
Cause
There are several possible causes: -
- an individual backup image file was deleted from the image location, or file level corruption occurred some time after the backup
- backups may be created in a corrupt state due to problem with backup Image Location (for example, disk error or unstable network connection)
- the backup is not corrupt, but a read IO error occurs during the verify or recovery process
- a system resource issue in Windows may cause verify/recovery process to fail
Solution
Perform the following steps to isolate the problem: -
1) attempt to verify the backup again using Verify Images page in Kaseya UI, in case there was a temporary problem with access to the image location
2) if the problem occurs only in the current backup set, force a new full backup by re-applying the Image Password on the affected backup agent
- password does not need to be changed, just reapplying the same password again will force the next backup to be non-synthetic full backup
3) if the problem still persists in the new set, copy the whole of the current backup set to another location. If the image location is a LAN share, copy to a locally attached drive. Attempt to verify from that location using the Kaseya Backup Local UI or Acronis Management Console ("validate" function). If this is successful, there is a read IO problem affecting the original image location
4) if the problem still persists after copying the set, create a new backup directly in that location and test if this can be verified. If this is successful, there is a disk error or network problem causing corruption of backups created in the original image location
If backups created in multiple locations cannot be verified: -
5) attempt to verify the backup from a different backup agent machine
6) boot from the Acronis "Universal Restore" CD and test the following: -
- "validate" existing backups. If successful, there is a problem in Windows affecting the verify/recovery process.
- take a new backup from the boot CD, and check if that can be validated. If successful, there is a problem in Windows causing backup to be created in corrupt state.
If backups created from the recovery CD cannot be verified, there may be a hardware fault.
If the problem is specific to a network-based Image Location: -
- check network adapter drivers are up-to-date on the source machine and the server or NAS device hosting the file share
- ensure OS/firmware is up-to-date on file server / NAS device hosting the LAN share
- test the backup without any on-access AV software running on the server hosting the LAN share
- if the LAN share is on a computer running a Windows desktop OS (such as Windows XP or Windows 7), the problem may be caused by the concurrent connection limitations of this operating system. Try changing the auto-disconnect timeout as described here - http://support.microsoft.com/kb/314882 (!) we do not recommend using a workstation OS or “workstation class” hardware as the image location for large or multiple backups
- to further isolate the issue, test backing up to a network location on a different file server / NAS device
If the problem is specific to Image Location on a locally attached drive: -
- run Windows checkdisk utility with repair option (chkdisk DISK: /r) on the Image Location drive
- test the drive for any hardware issues (refer to drive manufacturer for details)
- if necessary, replace the drive permanently
If the problem occurs with multiple image locations but only from Windows (not the Acronis boot-able media): -
- disable AV software
- monitor for any system resource issues during verify/recovery process (e.g. low available RAM)
If the problem occurs with multiple image locations from Acronis boot-able media as well as Windows: -
- test memory - https://kb.acronis.com/content/1669
- re-test using Acronis boot media on a different computer
Further investigation
If the problem cannot be resolved using the steps above, please provide Kaseya support with the following information: -
- logs from failed recovery and/or verify process
- screenshots of any on-screen error messages
- results of test steps described above
- Acronis Info report tool output (AcronisInfo.zip) from backup agent (if restore / verify is attempted from a different machine, provide the report from that machine too)
Applies to
Kaseya VSA (Backup module) - all versions