This document might help as well.
https://www.cisco.com/c/en/us/support/docs/unified-communications/unified-communications-manager-callmanager/18772-extension-mobility.html
You can run "show open ports regexp 8002" on CLI of all the nodes of your CUCM cluster.
You should see in the output if SDL connection for TCP port 8002 is established with peer nodes or not.
This will give you a fair idea about between which nodes ...
You can check this document for a detailed explanation about Database replication on CUCM and troubleshooting as well.
https://community.cisco.com/t5/collaboration-voice-and-video/troubleshooting-cucm-database-replication-in-linux-appliance/ta-p/3...
I am answering this assuming you are referring to "Cisco call manager traces".
It will very much depend upon the call volume but you can run the below command on each node in your cluster to check the number of trace files and the date/time they were...
Seems to be this defect :
https://bst.cloudapps.cisco.com/bugsearch/bug/CSCur52045/?reffering_site=dumpcr
Though it mentions CUCM 10.5 , i believe it should be same for 9.x as well.
Fix will require root access, would recommend opening a TAC case....
