I am attempting to set up an Open Directory replica server in Mac OS X Lion server 10.7.1 I have the master set up and working (as far as I can tell) fine. When I go to the second machine and attempt to set it up as an open directory replica, it looks like it works as well- the setup dialog runs through with no errors, and the replica server shows up on the master as ok. However, the replica server never show itself as being a replica - as soon as I refresh the view in server admin, it says Role: Standalone directory again. Sometimes it will show itself as being a replica briefly, but only until the server admin view is refreshed. How can I get the replica role to stick? Thanks.
The UI for configuring Open Directory isn't very good about reporting errors. Check the log (/Library/Logs/slapconfig.log, shown as the Configuration Log in the Open Directory -> Logs section of Server Admin) to see what really happened.
The standard problems with replica setup are SSH access (make sure you can SSH from the replica-to-be to the master and authenticate as root with a password), and DNS (make sure that when the replica looks up its hostname it gets back its IP address, and when it looks up its IP address it gets back its hostname).