openLDAP Master/Slave

["Byron Harris" <bharris@fp-usa.com>]

I've got LDAP working pretty well on two systems.  The master is a RedHat
ES3 system and the slave is an older RedHat 9 system.  It's all working
pretty well, the master replicates to the slave, authentications are working
well, etc., but I have one question or at least something I don't
understand.  It is my understanding that if you try to update a slave it
should give a referral to the master and the update is made to the master
which then replicates via slupd to the slave.  This is where my
understanding and what I see happening don't line up.  Here's my setup.

nfpmail, 192.168.12.1, is the master LDAP server
ncdp, 192.168.12.22, is the slave LDAP server
I've setup a local DNS domain of .fp
I also have a DNS entry of ldap.fp pointing to 192.168.12.1

My thoughts are that if the master LDAP server fails I will simply change
the DNS server to point to the slave machine until we get the master back on
line.  

For testing I don't want to be messing with my DNS, so I've been testing by
changing the /etc/ldap.conf file on the slave system.  Normally,
/etc/ldap.conf has "HOST ldap.fp", but for testing purposes I change it to
"HOST ncdp".  Authentications keep working, but writes don't seem to be
referred to the master.  Instead the local, slave database is being updated.
To test writes I've been using passwd at the shell prompt.

Any ideas are appreciated.
Thanks,
Byron