Unanswered: problems with online backup...include logs option
I am a newbie to this forum.
ENV: DB2 v9, AIX 5.3
We are backing up the database to TSM. The archive logs go to a different managementclass (primary DISK stgpool -- BUPOOL3) where as backups are going to tape. This is the backup command that I am using:
db2 backup database $Dbname online use tsm parallelism 4 include logs
Sometimes (there is no pattern) the backup fails with the following error:
SQL2025N An I/O error "-50" occurred on media "TSM".
Earlier we thought that probably there are insufficient tape drives (mount points) available but that wasn't the case. The db2diag.log shows the following error:
ADM8010E Backup was unable to copy requested log file "S0000086.LOG" for inclusion in the backup image. The backup has been aborted.
Now it seems the problem is the "include logs" option that we are using with the backup command. After researching there's not much I could find other than "The error occurs when archiving and retrieving happen simultaneously".
Is there a way to get around this problem? How can I set up a different management class for the logs that are included with the backup. Will this affect the backup performance and the restore?
You should be able to use the "include logs" option this way. The problem is that during the backup, DB2 might determine that it needs to include an archived log and thus needs to retrieve it. Like I said, I do not know tsm, but it might have a problem trying to retrieve a log file while it is backing up the same server. Using this method, it will try the retrieve from disk first, then tsm if that fails, although retrieving from disk almost never fails.
I *think* I have figured out the problem about the backups failing occasionally.
The problem is that the archive logs even though go to disk but eventually ending up on the same tape where backup is being written to. So backup fails when the tape is trying to read and write at the same time.
So I think allocating a different storage pool to backups could help solve the issue.