Environment
------------------
NetBackup 6.0 MP7
Linux Master Server
We just purchased a NetApp VTL and I have it deployed. This weekend was
our first weekend to use the VTL completely. I created 80 virtual drives
using virtual tapes that map to the barcodes on my physical tapes in my
Spectra Logic library.
One of the things I was stoked about when deploying the VTL was the
thought of creating a ton of drives and kicking off most if not all of
my policies at the same time. Coming into work this morning, however,
I've discovered maybe that wasn't the best idea.
When I kicked off my vault operation, it ejected over 1.5 times the
number of tapes I'm used to seeing on a Monday. Perplexed, I started
looking at the attributes on the tapes to see if I missed something when
I setup the vault policies for my new virtual drives. I'm noticing a lot
of tapes that are maybe 10% - 20% full that are being ejected.
Here's my theory:
The time table in my vault profile is 20 days ago to a day and a half
ago. Since I have so many virtual drives, all my jobs got a new scratch
tape, instead of some policies appending their job to an existing tape
in the same volume pool. So rather than having some tapes with 2-3
backups written on a single tape, all 100 something backups I wrote over
the weekend is on its own tape. I came in this morning and kicked off my
vault profile, all the tape (except the ones written too within the last
day and a half) match the criteria for the vault profile and were slated
for eject. At this rate I'm going to burn through my physical tapes in a
week or less.
What I've done for the time being:
* I've disabled multistreaming on some of my faster clients. I'm
assuming this will cause that job to put all the mount points on the
same tape instead of giving each mount point it's own tape (at the
expense of running longer).
* I've set my vault time table for 20 days ago to 3 days ago. I'm hoping
this will leave some tapes in my library to fill up more.
* I've changed my storage unit groups "Maximum Concurrent Write Drives"
to 6 (down from 20).
Questions:
I cut my teeth in Backup and Recovery on Legato NetWorker. I remember a
screen in NetWorker that showed me the % full of all the tapes in my
library. Each day I would eject everything that was 100% full and leave
everything else (even tapes that were 99% full) in the library to have
more backups written to them the next night. In the time I've been with
NetBackup, I've always wondered if there was a similar setting of "If it
isn't over X% full, leave it in one more night". I've never lost sleep
over not finding this setting because having the vault time setting of
20 days ago to 1.5 days ago has always ejected tapes that were mostly
full. Now I'm very interested in seeing if there is some setting in
Vault or elsewhere in Netbackup that will retain tapes in the library
until they've been as fully utilized as they are going to get.
I've pulled up the Vault Admin guide. I'm reading it, but thought I'd
toss this question out on the list here for feedback.
Thanks.
- Heathe Kyle Yeakley
_______________________________________________
Veritas-bu maillist - Veritas-bu AT mailman.eng.auburn DOT edu
http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu
|