Re: MirrorMode VS load balancing

[Michael Ströder <michael@stroeder.com>]

Brett @Google wrote:
> On Tue, Jun 30, 2009 at 10:19 PM, jakjr <joao.alfredo@gmail.com
> <mailto:joao.alfredo@gmail.com>> wrote:
> 
>     Why not use a Multi-Master replication for this situation ?
> 
> I don't propose one or the other. But here are some thoughts against :
> 
> http://www.watersprings.org/pub/id/draft-zeilenga-ldup-harmful-02.txt
> 
> The core issue for me seems to be conflicts with determining who has the
> "newest" data, and efficiency of transfer. If replication is
> predominantly in one direction, the replication works better with less
> latency and there is less opportunity for conflicts.

Well, even with simple master-slave replication there can be subtle
problems if an application writes to the master (even through
slapo-chain) and reads immediately from the slave.

One has to carefully examine the behaviour of the LDAP client
applications before making decisions on replication and fail-over scenarios.

Ciao, Michael.