Dear Managers:
I recently submitted a question concerning vdump of cloned filesets being
the possible cause of system hangup problems. I am still working on this
issue and have not yet been able to summarize.
My company has renewed its Tru64 software support license with Compaq and I
heard some REAL interesting responses to my questions about using vdump on
cloned, mounted file sets when I called for support. The system I
discussed with him is our Alpha server 1000 with v4.0B.
The software support rep. told me two things I did not want to hear as they
completely go against key issues I've learned so far about vdump and cloned
file sets:
1. I should "never" need to use cloned file sets for any vdumps, level 0
or otherwise, and should always vdump the actual file sets regardless of
open files.
2. I should "never" have to go to single user mode to do a level 0 vdump of
a file set, either /, or /usr, or other...That there is a copy of any open
file on disk and it will be on the dump and safe to restore.
I have understood that cloning file sets is for level 0 vdumps. Is there
another purpose for them if not backups?
I have always understood that to ensure level 0 dumps are good, do them
from single user mode (if not cloned file sets). As an example of this, I
quote a passage by Nemeth, Snyder, Seebass and Hein from their book, UNIX
System Administration Handbook 2nd edition, p. 191:
"Filesystem activity should be limited during dumps, because changes can
cause dump to make mistakes. ...An inconsitency in a level zero dump can
make it impossible to restore the filesystem; therefore, the filesystem
shoud be absolutely stationary while a level zero dump is being done."
Perhaps someone can shed some light for me on what is actually happening
when dump/vdump records files that are open that would cause file set
restore problems?
Is there any truth to what Compaq support is telling me? If not, how does
one update Compaq support's knowlege base?
Any thoughts or confirmations on this is greatly appreciated.
Thanks!
Steve
-----------------------------------
Steve Shanks (shanks_at_probita.com)
Probita, Inc.
4949 Pearl East Cir. Suite 300
Boulder, CO 80301
(303) 449-7665
Received on Wed May 05 1999 - 22:59:33 NZST