Re: MirrorMode behind fail over loadbalancer

[Buchan Milne <bgmilne@staff.telkomsa.net>]

On Monday 21 January 2008 16:49:39 Diaa Radwan wrote:
> We have two openldap 2.4.7 , configured as MirrorMode, We are planning
> to add load balancer in front of both servers into the production
> environment, We don't want too go through conflicts issues as it was
> stated before as messy process.
>
>
> ---------	---------
> .	.	.	.
> .  Srv1	.	.  Srv2	.
> ---------	---------
>    \                 /
>     ---- ------------
>        . LoadB   .
> 	.-------.
>
> As per my understanding, the load balancer(failover mode) is
> redirecting all traffic to the active server(srv1);

Actually, I would consider having two separate "server farms" configured, with 
two "virtual servers", one running on each. There would be one virtual 
servers


> if the active 
> server went down the traffic will be redirected to stand-by
> server(srv2). When srv1 goes online again the load balancer will
> redirect all trafic to srv1, while srv1 is in progress to get synced
> with srv2. The load balancer will not consider the sync process; it
> will just redirect the traffic.
>
> it was previously stated on the mailing list that there should be one
> write at a time. is there any conflict will occur when server getting
> bulk syncing and receiving updates(attribute level)/add requests as
> well?
>
> What happen if there attribute-level conflict? how to avoid it?
> suggestions are highly welcomed.