Subject: Re: Removing GNU tar and GNU cpio from src?
To: Robert Elz <kre@munnari.OZ.AU>
From: Greg A. Woods <email@example.com>
Date: 01/28/2003 15:46:59
[ On Monday, January 27, 2003 at 10:08:39 (+0700), Robert Elz wrote: ]
> Subject: Re: Removing GNU tar and GNU cpio from src?
> Dump silently ignores changes to files that are made while it was running,
> which is your definition of a buggy program.
As you no doubt know dump is not intended for use on a mounted (or
non-read-only) filesystem, and as I said before, those who use it on
live filesystems regardless should be aware of the implications.
I.e. if you use dump on a live filesystem then you know you're getting
an inconsistent backup. This might be OK if you know the files on that
filesystem don't have any important interdependencies, or if you are
able to restore the backup and verify the integrity of the files.
So, yes, dump does nothing to detect files that are modified during the
time the backup runs, but since it's not designed to be run on a
filesystem where such changes can happen this doesn't seem to be too big
of a problem.
On the other hand file archiving programs must be run on mounted
filesystems and since most people don't re-mount their filesystems
read-only just to archive some files, it only makes sense for archiving
programs to detect and report as errors those files which are modified
during the time the archiver was copying them. Just as you're free to
use dump on a mounted filesystem, you're also free to ignore some or all
of the errors reported by archiving programs.
Greg A. Woods
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