After you upgrade a CUCM cluster,users are unable to log in to their phones. Which three actions must you take to correct the problem? (3)
A. restart TOMCAT service on all servers
B. regenerate the Tomcat.pem certificate on the PUB only
C. reconfigure the Extension Mobility feature on the PUB and rebuild the PUB
D. regenerate the Tomcat.pem certificate on the PUB & SUB
E. reboot all servers in the cluster
F. restart the TVS and TFTP services on all servers
