Re: [gentoo-user] backup to a cold-swap drive

[Iain Buchanan]

Hi & thanks,

On Wed, 2010-04-28 at 17:31 +0200, Florian Philipp wrote:

> > Can md use one internal and one external disk in a RAID 1 setup, with
> > the external disk not always there?  Any other suggestions?
> >
> > thanks :)
>
> md would be extremely slow because it has to rebuild/resync the complete
> array.

so every time you unplug and re-plug the external disk, it will
essentially re-copy everything?  Damn, there goes that fine idea!

> If you can live with just one big partition as a backup (probably with
> separate /boot), you should replace fstab and grub.conf on the backup
> medium and blacklist them from the files which you want to back up.

why wouldn't I backup fstab and grub.conf as well?  If my internal disk
dies, I assume I'll swap them over, meaning grub and fstab will have to
be the same.

> Concerning the backup tool, I would use `rsync --delete` plus all
> relevant switches for permissions, times, acls, etc. If you use another
> tool, just make sure it doesn't put some metadata onto the backup medium
> and that it can delete files which no longer exist on the original medium.

I was thinking of rsync, but I didn't want to do it in an hourly cron
fashion, I was hoping for some "gamin" alteration-triggered idea.

> With regard to your requirement to just 'pull the cord' without
> umounting it:

I wasn't thinking of pulling the chord without unmounting, I was
thinking of the machine dying, hence leaving the disk in a non-shutdown
state.

thanks for the tips :)  rsync will at least get me going quickly.
Yesterday I tried iotop to with dd - some slowness but otherwise quite
nice.

-- 
Iain Buchanan <iaindb at netspace dot net dot au>

Real computer scientists don't comment their code.  The identifiers are
so long they can't afford the disk space.