Nightly backup never finishes

[remfonseca]

I have Retrospect version 6.0.193. Every night I backup 10 different Mac computers. I have an OS X server, a FileMaker Pro server and my computer is the host computer for Retrospect. I launch backup at 10pm every night from my computer, an iMac G4.

 

I use an Exabyte VXA tape drive. All 10 computers used to fit in one VXA cartridge (V10, 107m). I do a recycle backup (instead of normal) because I do not want incremental backup, I want all computers to fit in one tape cartridge. I am not here at night to switch and put another one in to finish the backup. However, lately the backup is requesting a 2nd tape even though it never did before. It used to do this (for some strange reason) when tape drive needed cleaning, but now even that does not fix it. I know it may be that user computers just have more info, but I have tried excluding application files and still backup will no longer fit into one tape cartridge.

 

What else can I look at?

[rang]

Honestly, it sounds like the user systems may simply have too many files to fit on one tape. You can get an idea of how much data needs to be backed up by using the preview function (though it takes a long time since it has to scan all the files).

 

When your backup requests a second tape, you can stop it, and check how much data was written to the first tape. If the amount of data stored on tape seems too low, perhaps your drive needs cleaning or you need a new tape. (The reason less data fits when the drive is dirty is because of error correction -- the drive will detect as it writes that some of what it wrote was not readable, and write it again.)

 

Mac OS X seems to share fewer system files between computers than Mac OS 9 did (thus requiring additional backup space) because of the prebinding that happens when the system is updated or applications are installed.

 

If you have the budget, you could get a second tape drive....

 

Why are you not using incremental backups, though? If you did a "normal" backup once a week or even once a month, and then incrementals the rest of the time, you'd rarely have to change tapes.

[remfonseca]

The back up always stops after backing up 8 computers, so it does seem to need more space for the last 2 computers. However, this is only a recent thing (which I guess could mean that the users just have more info). The thing about the Normal vs. the recycle backup though, I have tried to do a normal backup using a brand new tape and I still run out of space.

 

Maybe you are right, I may need to get a 2nd tape drive.

 

Thanks for your explanations though. They were helpful.