Re: [Gluster-devel] Server-side AFR + Failover and mixed server/client-side AFR

[gordan]

On Wed, 7 May 2008, Krishna Srinivas wrote:

> > > > >  Is this an issue in server-side-only AFR? I have two servers which
> > > > > are also clients of themselves, and they both list their local 
> > > > > subvolume first and
> > > > > remote subvolume second. Is this a problem? What are the possible
> > > > > consequences of this?
> > > >
> > > >  It will be a problem. The "first" subvol is always the "lock" server.
> > > >  Consider a case where you are creating a file simultaneously
> > > >  on two clients, only one of them should succeed. If AFR's
> > > >  subvols order are not same, chances are that both client
> > > >  returns success for file creation with same name.
> > >
> > > Hence you have "option read-subvlume" to speeden the
> > > read() calls so that it can be done from local subvol.
> >
> >  So, what happens if the "lock" server is the one that goes down?  Will that
> > render the whole AFR cluster inoperable, at least for writes?
>
> If first server is down, the second one is tried and so on. The cluster remains
> operable.

Does the lock state remain for the locks when the primary/lock server 
dies? If so, how?

Gordan