File under things you shouldn’t see too often: A few weeks ago I was supporting Greg Casas, an engineer at our company that was working on upgrading a customer’s Cisco collaboration environment. Everything was going well until he started upgrading Unity Connection. The upgrade of connection would get through the refresh upgrade portion, but would fail after it rebooted and started working on the rest of the upgrade. After some wrestling and a TAC case we discovered that the issue had to do with the Unity Connection server FQDN being too long. Just for example, let’s pretend that the fully qualified domain name for this system was unityconnection1.ilovesamplefives-voicemailsystem.samplefive.local, ok, yeah it’s a ridiculously long name, but we ran into a name about that long at the customer site. With version 8 there was not an issue with the super long FQDN, however the upgrade to 10 failed as a result. I’m not sure, but either the database structure changed with the upgrade or the field that the name was stored in went from just storing the name to the FQDN. In either case, the limit for that field in version 10 is 63 characters.