We are experiencing this issue multiple times with our FMC 4600 on cluster setup after we upgrade to 6.7. I hope cisco finds a way to get this resolve soon.
1- pmtool disablebyid vmsDbEngine
2- chown casuser:casusers /var/opt/CSCOpx/MDC/log/operation/sydb.out
3- pmtool enablebyid vmsDbEngine
4 - verify if service is running after enabling it - pmtool status | grep vms
5 - Try logging in to FMC. It should work now. Sometime it take 5min.
