[OpenAFS] Re: Vos functions and clones and shadows
Tue, 26 Jun 2007 18:04:54 -0400
On Jun 26, 2007, at 5:50 PM, Adam Megacz wrote:
> I've updated the FAQ with the contents of this thread.
>>> What if you create a shadow volume which has the same name as a
>>> volume which exists elsewhere? I assume that this would normally
>>> work, since the shadow doesn't get into the VLDB. If then you
>>> made the shadow volume live, would it delete the VLDB entry for
>>> the original volume? Perhaps without deleting it from the other
>> Your assumption is correct, and the answer to all the above questions
>> is yes.
> What if you then run "vos syncvldb" against the server holding the
> original rw volume? Will the volserver with the rw volume obliterate
> the formerly-shadow volume's entry?
We believe so, yes. At least, that's what's supposed to happen. IMHO
this is a feature, not a bug, or it is for our purposes. Consider
AFS servers goes down hard, looks like a multi-day outage. The
appropriate shadows are promoted to production, even though they're
five hours out of date. A few minutes later, the failed server
springs back to life. What's better: to let the out-of-date shadows
run, or to immediately recover/restore the production data of the
last six hours. IMHO it's the latter.