Re: Backup

["Timothy C. Phan" <tphan@iqrinc.com>]

Hi,

  Thank for the recommendation.

  One addition question,  if I backup using tar with -r (--append)
  and -N (--newer) options to the end of the tape, how would
  I go about extract or restore the files if the files have been 
  modified on the daily basis and I do this append with newer backup
  daily?

  Which mail order place has the best price on this HP DAT drive?
  Thanks

kmself@ix.netcom.com wrote:
> 
> On Tue, Jun 20, 2000 at 09:57:48AM -0600, Dean Allen Provins wrote:
> > >
> > >
> > >
> > > Hi,
> > >
> > >   I'm thinking to get a scsi backup tape for the Potato
> > >   box.  I'd like to know what is the recommended drive
> > >   and what software should be used.
> > >
> > >   I also have this dump question.  Would the backup software
> > >   append the backup files to the end of the tape or overwrite
> > >   it everytime?
> > >
> > >   TIA!
> > >
> > > ---
> > > tcp
> >
> > I use an HP DAT drive (35xxx - now called Surestore, I think).  Its
> > been use for about 5 years (every night) without a problem.  I've used
> > 'tar' and 'dump' and both work just fine.
> 
> I'll second the Surestore recommendation.  I've got a 2GB DAT which has
> been used a little less frequently <g>, but does a great job.  Note that
> if you plan on aquiring more than about 15 tapes, the cost point
> between DAT and Travan/QIC breaks down about even.  DAT is solid,
> dependable, proven technology, and the media are cheap and reusable.
> Just what you're looking for in a backup.  The downside is that
> capacity, relative to today's drive sizes, is somewhat limited.  I can
> get ~4GB compressed, which works for me, but you'll have to look at
> higher capacity tape drives for your 9-40GB disks out now.
> 
> > Whether or not the software appends or not, is in part predicated on
> > where the tape is when the run gets going.  Device /dev/nst0 doesn't
> > rewind, while /dev/st0 does.  If the backup software always rewinds,
> > and doesn't search for an EOF marker before writing again (i.e. knows
> > to append) you'll be out of luck.
> >
> > If you use commercial software, check the specs first.  If you write a
> > simple 'tar' script, you can do what you want.
> 
> On this.  Unless you have specific requirements to meet (eg:  management
> can't keep from fucking with a technical decision), I'd choose the
> simplest backup methods possible.  My own local backup script is:
> 
>     #!/bin/bash
> 
>     # Create backups of /etc, /home, /usr/local, and...
> 
>     mt rewind
>     tar cvf /dev/nst0 /etc
>     tar cvf /dev/nst0 /home
>     tar cvf /dev/nst0 /usr/local
> 
>     # and selected /var directories
>     tar cvf /dev/nst0 /var/backups
>     tar cvf /dev/nst0 /var/cache/apt
>     tar cvf /dev/nst0 /var/lib
>     tar cvf /dev/nst0 /var/log
>     tar cvf /dev/nst0 /var/www
>     mt rewoffl
> 
> Tar isn't the sexiest thing out there (honey is <g>), but damned if it
> doesn't work, and if the tools for accessing archives aren't available
> on every flavor of Unix, and most lesser operating systems, not to
> mention boot, rescue, and minimal installations of Linux.  You *will* be
> able to get at your data.
> 
> Other general recommendations -- dump, cpio, and apio.  I'd generally
> *avoid* using an integrated backup management solution -- far less
> portable, and you may *not* be able to get at your data, unless you are
> part of a large and well-supported organization.  You get some plusses
> -- usually a searchable index or other log of what was archived, but it
> costs you in terms of flexibility.
> 
> --
> Karsten M. Self <kmself@ix.netcom.com>         http://www.netcom.com/~kmself
>   Evangelist, Opensales, Inc.                       http://www.opensales.org
>    What part of "Gestalt" don't you understand?      Debian GNU/Linux rocks!
>      http://gestalt-system.sourceforge.net/      K5: http://www.kuro5hin.org
> GPG fingerprint: F932 8B25 5FDD 2528 D595  DC61 3847 889F 55F2 B9B0
> 
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