Problem seems to have resolved itself. May have been between keyboard and monitor.
I just checked the access and error logs but didn’t find anything that made sense to me. I cleared the logs and tried creating a host through the web GUI and it didn’t work. No error message, it just closes like it worked.
The problem might have been that I was using the MAC address for the name. Apparently that isn’t allowed even though I remember the full host registry and inventory doing that on its own.
Anyway, it just worked twice with a random hostname and a MAC address so it appears to to be working correctly. I swear this didn’t work yesterday, however.
Thanks very much for taking a look at this.