Path: utzoo!attcan!uunet!cs.utexas.edu!rice!sun-spots-request
From: elsie!ado@alw.nih.gov (Arthur David Olson)
Newsgroups: comp.sys.sun
Subject: Crashes using SunOS 4.1's "dump" command in multi-user mode
Keywords: SunOS
Message-ID: <9539@brazos.Rice.edu>
Date: 2 Jul 90 16:38:24 GMT
Sender: root@rice.edu
Organization: Sun-Spots
Lines: 16
Approved: Sun-Spots@rice.edu
X-Sun-Spots-Digest: Volume 9, Issue 245, message 10

As I understand it, the reason for doing dumps in single-user mode is to
ensure that the file system being dumped does not change in mid-dump
(since a mid-dump change could make the dump useless).

Since umounting a file system (or mounting it read-only) guards against
mid-dump changes, doing so should be an alternative to going single user.
In fact, that's what we've done here for quarterly level-zero dumps; we'd
go single-user to do the root and /usr dumps, then return to multi-user
mode, umounting, dumping, and remounting the other (large) disk partitions
in turn.

June 30 was the first time we'd tried doing this under SunOS 4.1.  We
experienced the crashing that's been reported here previously by
others--despite our careful umounting.  Oh well.

	Arthur David Olson   ado@alw.nih.gov   ADO is a trademark of Ampex.