Re: [GENERAL] PITR and tar

Jim C. Nasby wrote:
> Moving to -docs...
>
> Does anyone know what the history of the docs saying that GNU tar had
> issues with files changing underneath it? According to this report it's
> actually BSD tar that has the issue.

As I remember, Tom was the one who found that GNU tar would return a
non-zero exit status if the file changed during backup, so you couldn't
determine if the backup was successful based on the exit code.

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>
> On Wed, May 09, 2007 at 10:19:05AM -0700, Jeff Davis wrote:
> > On Wed, 2007-05-09 at 11:40 -0500, Jim Nasby wrote:
> > > Actually, looking at the docs, the problem is with some versions of
> > > GNU tar. AFAIK bsdtar is perfectly happy to archive files that have
> > > changed from underneath it.
> > >
> >
> > $ tar --version
> > bsdtar 1.2.53 - libarchive 1.3.1
> >
> > That fails to create a file in proper gzip format when the files are
> > concurrently modified.
> >
> > However,
> >
> > $ tar --version
> > tar (GNU tar) 1.14
> > Copyright (C) 2004 Free Software Foundation, Inc.
> > This program comes with NO WARRANTY, to the extent permitted by law.
> > You may redistribute it under the terms of the GNU General Public
> > License;
> > see the file named COPYING for details.
> > Written by John Gilmore and Jay Fenlason.
> >
> > That _appears_ to work.
> >
> > Perhaps FreeBSD users should take notice of this problem. It's certainly
> > not a postgresql problem, but I know there are a lot of freebsd users
> > here, and using tar on fast-changing data may be rare outside of
> > postgresql.
> >
> > Regards,
> >     Jeff Davis
> >
>
> --
> Jim Nasby                                      decibel@decibel.org
> EnterpriseDB      http://enterprisedb.com      512.569.9461 (cell)
>
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  Bruce Momjian  <bruce@momjian.us>          http://momjian.us
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