[rescue] Oracle making just a little harder to keep old machines in use
rsk at gsp.org
Mon May 10 07:00:53 CDT 2010
On Sat, May 08, 2010 at 11:05:50AM -0400, Patrick Finnegan wrote:
> Why won't (GNU) tar work? It does everything that you say you are
Well, yes and no.
Tar doesn't have code to cope with filesystems that are changing
as they're being read.
It runs in userspace instead of reading the raw device.
While it has some incremental backup capabilities, it's not readily
usable in the same way that dump's incrementals are. Yeah, you can
wrap some shell around it and get close, but it's awkward.
It doesn't know how to split its output across multiple volumes.
Tar's "catalog", if you will, is spread throughout the archive and
not at the beginning. Whether this is good or bad or indifferent
depends, but I think for backups (as opposed to archives) it's not
a good thing.
It does have the merit of creating archives that are very portable.
What I'll argue that we (FSVO "we") need is a portable version of
dump that runs on the appropriate set of currently-extant open-source
'nixes (read: the BSDs, (open)Solaris, and the Linuxes), which can
cope with the appropriate set of currently-extant filesystems, which
creates output in a portable-enough format that it can be read on
any of these, and which has had some thought put into its design in
order to reflect the changes that have happened since the days of
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