Aaron J. Grier wrote:
> On Fri, Aug 08, 2008 at 03:38:25PM -0700, Steffan Vigano wrote:
>> "the LTO tapes only hold 100GB natively, and you can't backup a file
>> system with dump that's larger then the actual capacity of the tape."
> [...]
>> A) Was there any truth to his original statement?
> 
> only if compression is not used, and the partitions are full.  (or if
> compression is used, and the partitions are full of non-compressible
> data.)
>
In my younger days I did manual backups using dump, and when it
hit EOT it would ask for a new tape and wait for you to change tapes
and hit y to continue.  Made full backups of large filesystems
a pain, as you couldn't just start it in cron at let it run (well
actually I did, I had it kick off on Saturday morning at a time
that would let it be finishing the first tape about the time I
planned to stop by to change the tape.  Fortunately it fit on
two tapes so I wasn't stuck there for hours).
  Originally, Amanda was not able to backup any filesystem/directory
larger than the capacity of a single tape. The ability to span
a dump image across multiple tapes was added to Amanda awhile
back.  Amanda has always had the ability to use tar instead
of dump, enabling you to back up subdirectories that would fit on
a single tape.
   Personally, I feel that having a multiple tape dump image just
increases the odds of a failed restore, as well as making bare
metal recovery without Amanda more difficult. YMMV.

Frank

-- 
Frank Smith                                      fsmith AT hoovers DOT com
Sr. Systems Administrator                       Voice: 512-374-4673
Hoover's Online                                   Fax: 512-374-4501