[OpenAFS] Re: Read-only replication

Andrew Deason adeason@sinenomine.net
Thu, 17 Jun 2010 14:03:53 -0500

On Thu, 17 Jun 2010 19:35:13 +0100
Simon Wilkinson <sxw@inf.ed.ac.uk> wrote:

> > As you mentioned, they can also 'kinda' be used for backup purposes,
> [ snip ]
> > I definitely wouldn't recommend that for home dirs or anything like
> > that, though, since from the user's perspective it looks like their
> > data just suddenly went back in time by a day. Usually it's not much
> > better than just having real backups.
> I'd strongly recommend considering them for this use - alongside a
> real backup solution.

Yes, that's fine; I meant for doing that automatically. I was trying to
advocate against two things, which some people have at least thought
about doing: (1) having that _replace_ a backup system (that is, not
having any other backups), or (2) automate RO->RW conversion in the case
of a failure.

(1) is obviously a bad choice because you only get one, and the data is
still in datacenters on servers, etc etc. (2) is bad for homedirs
because the data suddenly reverts to what it was a day ago, which is
confusing at best. If you always treat it as a normal backup recovery
scenario...  well, yeah, you have to go back in time no matter how you

Andrew Deason