Kolab2 Slapd hanging - master/slave replication issues

[Stephan Buys]

Hi all,

Today I'm the one in need of advice :-)

We have a big Kolab2 server with about 350 users on it and 2 slave servers
in remote geographic locations. The slave servers have between 50 and 100
users each.

We deployed Kolab2 on Sunday and have since had several issues:

1) slapd keeps on hanging. I suspect that this is due to the strain taken by
slapd as it needs to service, "uid requests", "mail routing", "sasl auth", etc.

2) When slapd hangs we need to do a db_recover to get it back up and running.
After having to run db_recover on the slave as well as the master servers the
databases have now become inconsistent.

So my questions:

1) What can I do to make slapd more robust? Pre-forking, more children processes?
The main server is running at load average of 3 at the moment which I am sure 
compounds the problem...

2) How easy is it to re-sync the master-slave databases? Can I stop the servers,
copy the master dbs to the slaves and start up again?

Any tuning/optimisation tips would be greatly appreciated.

Regards,
-- 
Stephan  Buys
Code Fusion cc.
Tel: +27 11 673 0411
Mobile: +27 83 294 1876
Email: s.buys at codefusion.co.za

E-mail Solutions, Kolab Specialists.
http://www.codefusion.co.za