Problem
- the following warning message is logged after an incremental or differential backup: -
Older backup files were overwritten during the backup process. This error caused some backups to be invalid, and thus removed from the database. The backups were likely overwritten due to a faulty NAS, too many machines writing to the image location at the same time, or spanning the backup at too small of a file size.
- from the reported size of the incremental or differential backup, it can be seen that it actually created a full backup
- the original full backup from the set, and prior incremental backups, have been deleted
Cause
This typically occurs during an incremental or differential backup if there is a problem with the existing backup chain, for example if the base (full) image or earlier incremental archives are no longer present. It can also occur if there are network issues when backing up to a LAN share, and the backup process cannot access previous backup images.
In such cases, Acronis will automatically create a new full backup instead of an incremental, and previous backups in the set will be removed.
Resolution
To get more detail of what caused the problem, review the Acronis log from the incremental backup in question (from Backup Logs page, use the hyper-link in the "Result" column to download XML file).
Depending on the environment, and details in the log, check the following: -
- backup images are not moved or deleted in the middle of a set
- the Image Location disk is not removed or swapped out
- if Image Location is a network share, ensure connection is stable and destination server/NAS is always online during backup window
Applies to
Kaseya VSA (Backup module) - all versions