Folks,
We're wanting to upgrade from BudTool-4.6 (with patch 10) to bt-4.6.1a
(plus its patch 2.Jumbo), in order to enable a NetApp OS upgrade
(OnTAP 5.2.3 -> 5.3.x), per the applicable compatibility matrix,
and we have run into a pretty serious issue that perhaps others of
you have already dealt with.
As background, at our site, our BudTool host is Solaris-2.6/SPARC, which
controls a tape library's robotics & uses NDMP to tell our NetApp to
back itself up to a SCSI-connected tape drive in that library (other
tape drives are SCSI-connected to the BudTool host, and are used to
backup other clients by various BudTool methods).
While reading through the BudTool-4.6.1a Release Notes, I found:
Split Images
If a backup request is too large to fit on one tape, BudTool can
split the backup image across a maximum of three tapes. BudTool
does not support backup requests that require four or more tapes.
Now if you're like me, you have a NetApp filesystem which is big
enough to be split across 4 or 5 DLT7k tapes. In fact, we've been
backing up such a filesystem for a couple years now, and have even
done a number of single-file or single-directory restores from such
backups, without any problems. We also use "btcp" to make offsite
copies of these backups onto a DLT4k stacker, which of course splits
such a backup image across even more tapes (up to 5 or 6).
Naturally, after a lot of slow, deep breaths, I immediately did a
little test, and was able to successfully restore a single file
from a recent full backup which is split across five tapes. As
is typical of dump/restore, it had to load and read all five tapes
before the restore was complete. Although the file was a pretty
recent one, and has a "high" inode number, I can't be sure which
of the tapes contained the file I restored.
Anyway, when I called PDC (yeah, Legato has farmed out all our BudTool
support calls to PDC), they checked with Legato, who told them that yes,
this is a known problem, and it has "always been that way", it's not
something new introduced between bt-4.6 and bt-4.6.1a (and its subsequent
jumbo patch). Specifically, I was told that if I tried to restore
something that resided on that 4th (or 5th) tape, the restore would fail.
The PDC support person also told me that Legato would not be issuing
any more patches to BudTool, so this problem will apparently not be fixed.
Ain't it great what $30k worth of software purchase and $6k/year of
software maintenance (over the course of 2-3 years) can buy you?
And any guesses as to who we're _not_ going to use to replace our
BudTool installation & maintenance?
At this point, I'm not sure what to say, other than to ask if anyone
else out there has used bt-4.6 or bt-4.6.1a to backup and restore a
filesystem that spans more than three or four, or more tapes, and
of course to please let me know your results. I'd particularly like
to know how and/or under what circumstances this split-image limit
comes into play.
Well, I'm off to break up that backup request into smaller ones.
It's a lucky thing that 200GB filesystem is mostly divided into qtrees
for each of our research centers.
Regards,
--
Marion Hakanson <hakanson(a)cse.ogi.edu>
CSE Computing Facilities