Subject: Re: Moving /var/cron/tabs
To: John Nemeth <jnemeth@cue.bc.ca>
From: Manuel Bouyer <bouyer@antioche.lip6.fr>
List: tech-userlevel
Date: 12/21/1998 14:03:42
On Dec 19, John Nemeth wrote
>      You would also have to worry about /var/account, /var/at/jobs,
> /var/log, /var/mail, /var/msgs, /var/preserve, /var/spool, and
> /var/yp.  Clearly, there are many things in /var that need to be
> backed up to get a full system backup, which means this suggested
> change is completely pointless.  I really don't see what the problem
> is or why Manuel considers this to be a bug.

You're mixing log files with files that define how the system is
setup. Strictly speaking, things are worse than that:
/var/account, /var/log, /var/preserve and /var/spool contain only
log files. They can be lost, this will not affect system operations.
So don't backup them (I certainly don't want to backup the 1G logs
of my router !).
/var/at/jobs, /var/mail, /var/msgs and /var/cron contain user informations.
They should be backed up with users's home directory. You can add
/etc/master.passwd to this.
/var/yp and /var/db/pkg contain system informations and should be backed
up at the same time as the system binaries. If I can't restore /var/db/pkg,
backing up /usr/pkg is useless.

Now, from a practical point of view:
on my mail server, /var/mail is a separate partition, backed up alone.
On other system, it's an NFS mount point.
In case of a failure requiring a reinstall of a machine, loosing at jobs
is not a big deal to me. Users have been warned anyway.
/var/msgs is a link to a directory on the NFS home dir server, so that
it's accessible from all workstations. It's backed up with the home dirs.
/etc/master.passwd is saved with the system, it's enouth to me (in case of
a restore, they may not have their lasted passwd, but that's not a big deal).

The only problem I can see is /var/db/pkg and /var/cron, which describe the
system setup and behavior, and should be backed up with other system binaries.
But they lives on a partition which may contain big files I don't want to
backup.

--
Manuel Bouyer, LIP6, Universite Paris VI.           Manuel.Bouyer@lip6.fr
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