One of our customers had some problems with their UCCX 8.0 Subscriber node.
After restarting some services and eventually the entire server, RmCm subsystem would not start, it was stuck in INITIALIZING.
I looked at a couple of troubleshooting tips with no luck.
My colleague then opened a TAC case and eventually they fixed the problem.
It turned out to be some sort of replication issue.
Login to the UCCX Publisher
1. Cisco Unified CCX Serviceability – > DataStore Control Center -> Replication Servers
2. Click Disable CDS and HDS
3. Click Reset replication
4. Enable CDS and HDS