Verify Fails on Incremental Backup to Disk - BE 2010 R3
Backup Exec 2010 R3
I do incremental backups to disk on about 30-40 servers. Recently all of the servers being backed up were failing to verify, despite the actual backup looking like it ran fine. The catalogs seemed to represent everything accordingly and I could restore data.
I tried rebooting the server hosting Backup Exec, and also restarted the storage device (Snap Server), but this did not help.
The error on the verify:
The query for media sequence number -32768 of this media family was unsuccessful.
Ensure that all media in the family have been inventoried and cataloged.
I showed this to a colleague and he recognized that -32768 was the minimum value for a short integer. This led him to believe that we had somehow maxed out the number of media sequences possible.
What we found out was that the media set being used had the Append Period set to "Infinite - Allow Append". Our B2D device media is 1GB each, our incremental backups are around 200-300GB per day. I would assume that the media sequence number would get changed per backup job. So for example, my nightly incremental being 300GB, the highest media sequence number would be in the low 300's (1 media sequence number for each gigabyte, since the device media is 1GB each). I would also think that a full media event would reset the media sequence number in which case it would seem impossible to max out.
What it seems like is that with the Append Period set to Infinite, the media sequence number never gets reset, but just continues to increment by 1 until it reaches the maximum value for a short integer.
I resolved the issue by changing my Append Period to 1 hour. I don't know if this allowed the media sequence number to start over or what, but it did seem to resolve the issue for me.
In hindsight, I don't know why I would ever want the append period set to indefinite on a B2D scenario where the incrementals are only retained for 2 weeks anyway. I also don't understand how I would be able to restore anything if the media is improperly sequenced. Hope this helps someone...or maybe someone else can offer further explanation.
Aaron