We have also been looking at using a large diskpool.
It appears migration only uses one tape drive per node.
So, if you use TDP to back up 500GB to disk and then
run migration, it will only use one tape drive to
migrate that 500GB.

Is this true?

-----Original Message-----
From: nickpc AT US.IBM DOT COM [mailto:nickpc AT US.IBM DOT COM]
Sent: Tuesday, May 27, 2003 8:19 PM
To: ADSM-L AT VM.MARIST DOT EDU
Subject: Re: anyone using ATA disk systems
Importance: Low


Yep - have a maxsize on the 2nd DASD pool.  When migration kicks off from
the first DASD pool, the larger files will "skip" over the 2nd DASD pool to
tape.  It's just a 2 step nextpool configuration.  Plus, if the 2nd DASD
pool gets overfilled, it will migrate to the tape pool, so you won't get an
out of space condition.

Your storagepools would look like this:

Storage      Device       Estimated    Pct    Pct  High  Low  Next Stora-
Pool Name    Class Name    Capacity   Util   Migr   Mig  Mig  ge Pool
                               (MB)                 Pct  Pct
-----------  ----------  ----------  -----  -----  ----  ---  -----------
SCSIDASD      DISK           1000.0    00.0   00.0   90   70    ATADASD
ATADASD       DISK           1000.0    00.0   00.0   90   70    TAPEPOOL
TAPEPOOL      TAPECLASS         0.0    00.0   00.0   90   70

And the ATADASD pool would have a maxsize parameter on it of whatever you
wanted.

Nick Cassimatis
nickpc AT us.ibm DOT com

Think twice, type once.




                      "Rushforth, Tim"
                      <TRushforth@WINNI        To:       ADSM-L AT VM.MARIST 
DOT EDU
                      PEG.CA>                  cc:
                      Sent by: "ADSM:          Subject:  Re: anyone using ATA 
disk systems
                      Dist Stor
                      Manager"
                      <[email protected]
                      .EDU>


                      05/27/2003 03:41
                      PM
                      Please respond to
                      "ADSM: Dist Stor
                      Manager"






We've been thinking about a huge disk pool also.  What we would probably do
is client backup to SCSI disk first then migrates to cheap disk or Tape.
What I really would like is to control which backups go to Tape or cheap
disk based on size.  (We get great throughput restoring large files from
Tape - not sure if it is worth keeping them on Disk - small file restores
on
the other hand are killers on Tape.)

You can specify a maxsize parameter on a stgpool that a client will use but
this isn't used by subsequent migrations.  This works if I want my client
backing up to tape directly - but I don't want that - not enough tape
drives!

Is there anyway that this could be done? IE. Initially backup everything to
DISK - then basically control migration or Move Data based on size of
files.

Or is this just whacky thinking?!

Thanks,

Tim Rushforth
City of Winnipeg