Subject: Re: [vserver] Poll: High (ish) availability - how are you doing it?
From: Remigiusz Modrzejewski <lrem@sphere.pl>
Date: Tue, 27 Jul 2010 17:29:52 +0200

 Tue, 27 Jul 2010 17:29:52 +0200

On Jul 27, 2010, at 16:32 , Gordan Bobic wrote:
> 
>> I would be interested in any systems 
>> people have experienced that do an async replication between two 
>> machines, eg some process which uses inotify/dazuko/redirfs to watch for 
>> changes and then an async queue to merge changes to the second machine - 
>> the goal being to have a near realtime replica, but without the 
>> performance penalty associated with cluster filesystems?
> 
> It sounds like you are looking for lsyncd.
> 
> [...]
>> A more satisfactory solution seems to be active-active clustering.  This 
>> is now irrelevant to linux-vserver, but does anyone here have any 
>> experience of running active-active clusters of mailservers, webservers, 
>> etc?


Well, an excerpt from the front page of lsyncd reads:

#v+
When not to use:

File with active file handles (e.g. database files) Directories where many changes occur
(like mail or news servers)

In these cases e.g. DRBD (see http://www.drbd.org) might be better for you.
#v-

So if the OP is planning to use it for mail servers, lsyncd may not be a good idea.
Anyhow thanks
for pointing it :)

Kind regards,
Remigiusz Modrzejewski