Problem with dump(8)

[utzoo!decvax!harpo!zeppo!wheps!eagle!mhtsa!alice!physics!gill]

	We at BTL physics are having a problem with 4.1 BSD dump(8) on
our /usr file system. Seems that it tries to seek to some very high (and
occasionally negative) block numbers and gets a "shouldn't happen"
error. This happens in the middle of doing an epoch dump.

	I suspect this is due to the file system being active, and
haven't looked into the problem very much yet. Fsck says things
are fine.

	Has anyone else had this problem and/or solved it?
Does anyone know how dump is supposed to deal with (what we
used to call) "phase errors?" (when a inode points to different blocks
between the begining phase of the dump when maps are made and
the time the file is actually written to tape).

	As a great deal of long running (days) similuations are run on
our system (with output going to the file system we wish to back up),
we would like to avoid stopping these processes in order to do
dumps. This used to be possible under older dump programs.

	Thanx,

		Gill Pratt

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