On Mon, 7 Jul 2003 at 10:26am, Joshua D. Bello wrote

> I am currently experiencing problems with Amanda backup runs completing
> successfully, supposedly due to running out of tape.  I am using
> Amanda 2.4.3 on a FreeBSD 4.8-STABLE machine, backing up to 35/70GB
> DLT 7000 drive.  Compression is enabled on the drive, and we are also
> using compression within Amanda.  We are getting nowhere near the
> expected 70GB compressed capacity of the tapes.

Bad, bad, bad.  In trying to hardware compress already software-compressed 
data, it's going to expand.  Either:

Use software compression only, which allows amanda to better estimate tape 
usage (amanda will keep track of the compressed size of the FSs).  In this 
case, use the actual size of the tapes in your tapetype.

Or use hardware compression.  In this case, lie to amanda about how big 
your tapes are (you'll likely not get anywhere near 2X compression).  You 
save CPU cycles, but your tapelength will just be an estimate.

-- 
Joshua Baker-LePain
Department of Biomedical Engineering
Duke University