Disaster recovery.
Alex Zbyslaw
xfb52 at dial.pipex.com
Fri Oct 6 08:02:30 PDT 2006
Grant Peel wrote:
> Hi all,
>
> I currently keep file dumps of all filesystems on our servers on a
> secure raid 5 box, lees of course, the proc and swap dir.
>
> These dumps look like this and are done and transfered to a NFS
> filesystem in the /mnt/ dir.
>
> server1-usr-full-dump
> server1-home-full-dump
> server1-var-full-dump
> server1-root-full-dump
>
> So I have (all, I hope!) everything I need to rebuild a server should
> the hard disk completely crap out, or some script overwrites or rm's
> everything.
>
> I have never been in the position that this, ( a complete hard drive
> ), had to be done.
>
> so the question is ... if I have the dumps on one machine, and I just
> installed a new hard drive on another, in a nutshell, what are the
> steps to
> restore the failed server. Can I use the FreeBSD 'live' filesystem? Is
> ther a step by step (that I have not found) in the handbook somewhere?
Don't know that it's described anywhere, but in short below. You can
try it on a live server, don't actually do any newfs or restores!
Boot FreeBSD CD1 (pretty much any recent version ought to do unless
there were changes to dump or fliesystem format). E.g. a 5.4 CD ought
to restore a 6.2 machine just fine.
Newfs/bsdlabel/fdisk stuff probably from post install configuration, so
that you don't install any packages etc. This is where you need a paper
record of your disk slicing/partitioning.
Fixit shell and mount remote-partition-of-dumps using NFS on /mnt. This
may need some kldloads. I've gotten stuff accessible via SAMBA like
this so NFS ought to work. Needed to phutz with the load path for kldload.
Mount fresh e.g. / partitions on e.g. /mnt2 . I'm pretty sure you can
make new mount points as boot CD mounts root on a memory disk.
restore -f /mnt/server1-root-full-dump -root (check man page!)
Unmount /mnt and repeat for usr, home, var etc.
Note that you can gzip your backups and use a restore command like:
gzcat /mnt/server1-root-full-dump -root.gz | restore -f - -r
Dumps take longer but take up less space. I do the same thing and also
have incrementals. Always relied on figuring out what to do as I went
along if I ever needed to, hence the somewhat sparse nature of the above
procedure :-)
--Alex
More information about the freebsd-questions
mailing list