Reference article to consolidate information and provide troubleshooting steps for backup failures and performance issues.
Backups are taking a long time to complete or are failing.
What can cause a backup to fail with "The database update failed" or similar?
This error generally means that the backup appliance was unable to complete the database update for the backup. This more often than not is a secondary error to the actual root cause:
- Check further up or down the error log in the UI for other errors.
What can cause a backup to fail with "FATAL: Incomplete backup received from client."?
This error generally means that the backup appliance was unable to communicate with the Unitrends agent during the backup. Some items to check would be:
- Has the IP address of the client changed?
- Is the cabling between the client and the network plugged in? (Try a "ping" command from the client to the Unitrends backup appliance IP address)
- Did the client reboot during the backup, perhaps due to a Windows update? (You can check this by looking at the Windows system event lot for reboot events during the time of the backup)
- Does your firewall allow communication over the backup ports? For a list of backup ports see What ports need to be open for the Unitrends system?
- For Windows application backups, the Microsoft VSS agents are invoked during the backup. Please check the Windows Application Event log. The Unitrends agent reports major backup information events, warnings, and messages.
- If VSS errors are confirmed, restart the VSS service or reboot the client to reset VSS.
- Check to ensure that you have sufficient free disk space on the volume that is failing. A general guide is 10% free space for snapshotting.
- If the application is SQL Server, additional information can be found in Unitrends VSS SQL agent errors and warning messages
- Note that this is not an error condition and does not interfere with the backup; however, it can cause the backup to run slower, which may cause your backup window to be missed.
- For instructions on how to increase the change journal, see Journal wrapping or Journal Overflow Error | Expand Journal Calculations
- For an overview of how the NTFS change journal works, see this section of the Admin Guide.
- This error can sometimes result from an agent upgrade that was not successful. Check the troubleshooting steps in Host appears to be up, but had a network related error (-255).
- For a discussion of why files are skipped during backups see How to find skipped files in a "Yellow"(warning) backup
- Windows Hot Bare Metal backups failing
- System State backup failing, backup has warnings and Shadow Storage
- Backups Failing, /usr/bp full (moving logs.dir)
- Windows Backup Error: Task failed: Could not contact client after 5 attempts.
- Error: Failed to load bds metadata: Failed to backup disk
- VMware Backups Fail with FileAlreadyExists Error
- VMware Backups Failing with Error UUID Not Found
- Oracle Backup Failure - file create error
- Error: Combination of include and exclude list cause no volumes in list for backup
For more information to alleviate slow backup performance, see the following KB articles: