--On Thursday, October 23, 2003 21:40:13 -0700 Paul Yeatman <pyeatman AT ucsd 
DOT edu> wrote:

>> > Thanks for the reply.  Is there any such setting then that would
>> > perform what I was once was lead to believe chunksize could control,
>> > ie. specifying a file size over which a backup file should be written
>> > directly to tape, bypassing the holding disk?
>> 
>> For the filesystems you want to go directly to tape, use a dumptype
>> that specifies 'holdingdisk no'.
>>    I'm not sure why you would want to not use a holdingdisk (unless
>> you are using the FILE driver), it is generally more efficient to use
>> one.
>> 
> 
> Ah, great point!  I had forgotten about this.
> 
> The main reason I want to write some filesystems to tape (while writing
> others to holding disk) is that I have a config that backs up some
> laptops at noon, delaying desktop backups until 9p.  If I don't
> have enough holding disk space for one of the laptop's filesystems, the
> whole job gets delayed until 9p (which can screw things up when the
> laptop is no longer on the net at 9p).  I'm wondering if I specify for
> the filesystems of the laptops to always be written directly to tape if
> this would avoid this problem.

A larger holdingdisk (or smaller reserve) might be an easier solution.
Keep in mind that going direct to tape means you do all your backups
one at a time in series, but with a holding disk you can do several in
parallel (as many as you have dumpers).  Depending on how many (and
how slow) laptops you're backing up, you might be extending your
backup window too long and not having them finish before the laptops
go home.
   You might want to consider using BackupPC to backup the laptops
to a machine and then use Amanda to back that up.  It would require
more disk but it could be on a cheaper machine with a large IDE drive,
plus the users can do their own restores.

Frank

> 
> Paul
> 
> -- 
> Paul Yeatman       (858) 534-9896        pyeatman AT ucsd DOT edu
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