Apple Open Directory - Options Greyed Out after IP Change

I recently had to move a few Apple servers from one site to another for a client, and after the move the Open Directory was half-working (opens, lets you view users, but can't add/remove/edit). There were a few no-brainer fixes that i had to do initially, but at the end of the day the final fix was pretty much a bandaid.

Overall obvious steps:

1. Make sure your hosts file (/etc/hosts) is referencing the right IPs, in case anything changed.
2. Make sure the system is set to the right IP(s) for DNS.
3. Make sure the DNS Server records are updated to the new/correct IPs for both the forward and reverse zones.

The bandaid fix for me

In my case, when authenticating within the Workgroup Manager, it would lag and then eventually log in. Nothing in the logs about what was wrong, but the New User button was greyed out, as well as all of the fields on the actual accounts. For whatever reason i could reset passwords, not sure why. The ultimate fix was to add an additional network interface to the server, and set the IP address to the old IP of the server. Yep.

Troubleshooting Steps

• First i fired up tcpdump and did a filter of "port 53" to see if any DNS requests were going out or coming back in incorrectly. Didn't find anything there.
• Next i did tcpdump "host 10.x.x.x" (with the old IP of the server) on a hunch, to see if it was trying to send any traffic there. And yep, it was, on port 389 (LDAP).
• Knowing that, i did a grep for the IP in /etc and a few other places but couldn't find it, assuming it's in a binary DB somewhere or something. So the only solution is to make the traffic actually connect.
• In Networking, i added a new interface under the existing Ethernet, gave it the same IP of the server before the move, but with subnet mask 255.255.255.255. This allows the IP to respond without interfering with any other IPs on the subnet.
• After making that change, the directory connected and started working instantly.