[OpenAFS] HA RW vols

Arne Wiebalck arne.wiebalck@gmail.com
Wed, 4 Apr 2012 10:57:44 +0200


Am 3. April 2012 19:06 schrieb Ken Dreyer <ktdreyer@ktdreyer.com>:
> On Mon, Apr 2, 2012 at 12:06 PM, Jeff Blaine <jblaine@kickflop.net> wrote:
>> What have people had success with (existing solutions
>> in practice) for making RW volumes "highly available"?
>
> We have some content in AFS where it's acceptable to have a little bit
> of downtime, but we need to be able to recover with a minimum of
> hassle if we had an outage. In these cases, we mount the volumes
> explicitly as rw, but replicate them "behind the scenes" in cron. We
> can then use vos convertROtoRW if we need to quickly recover.
>
> It has its downsides, and it's not true multi-master RW, but it works
> in a pinch.
>
> - Ken

We use 'vos shadow' in a similar fashion as described by Ken: the RW
volume is shadowed at regular intervals and can be switched to in case
the main volume is not available.

Cheers,
 Arne