Backup ldap server

["sadique@vanillanetworks.com" <sadique@vanillanetworks.com>]

Hello

I did install and configure a primary ldap server. Is it possible to 
change the scenario to primary + backup ldap server where data are 
synchronized to each other on the time of updates? If so can I use this 
for fail over and load balanicing as we do in NIS? I am a newbie and if 
I ask a basic question please point me  to any relevant links I can 
follow in this regard.

Thanks
Sadique