[Gluster-users] Setting up a 2 sites replication with access to files from both sites

[Brian Candler]

On Tue, Apr 10, 2012 at 11:44:18AM +0200, François Legal wrote:
>      Anyway, I gave a test drive on this, and seem to be having locking
>      issues (users on both side can modify the same file without anything
>      preventing this). Can anybody comment on this.
> 
> That's just POSIX semantics. You could even have two users on the same
> machine accessing the same file and modifying it concurrently. If you want
> locks then (a) your application has to ask for them, and (b) other
> applications must also respect them [unless you're talking about mandatory
> locks, which are an unusual feature]
> 
>    Well, that kind of file sharing used to work great with samba (talking
>    about excel files shared via samba) on a single file system.

Ah, then the application probably *is* asking for a lock of some sort, but
that lock isn't being passed through. In theory it should be possible to
replicate this and generate a trace of the messages being passed through to
glusterfsd (but I'm afraid I don't know the best way to do that)