Call Manager - System Server - Node Name Change

[C_Noble]

I need some help determining the process and impact of changing my Call Manager names under System > Server.

For reference my cluster is version 14.  All nodes within the cluster were installed with a host name and the domain name is configured.  Additionally, all of the hostnames are in DNS and resolvable forward and reverse.

It appears the only change necessary is to update the Call Manager names under System > Server from IP Address to FQDN.

When I make this change what is the impact?  My Call Manager certificate is self-signed.  Will it be regenerated by actioning this change?  Is there any danger to the ITL files?  Should I enable pre8.0?

I think I found the documentation for this change but the wording is a bit muddy.  Any thoughts?

https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/admin/14SU2/adminGd/cucm_b_administration-guide-14su2/cucm_b_test-adminguide_chapter_0100011.html

[C_Noble]

For reference, my cluster is also in mixed-mode.

[faiqarani1999 · Accepted solution]

Changing the Call Manager names from IP Address to FQDN under System > Server in a Cisco Unified Communications Manager (CUCM) cluster version 14 should have minimal impact if your DNS setup is correct. The self-signed certificate should not be affected by this change, as it is tied to the server's hostname rather than its IP address.

There shouldn't be any danger to the ITL (Initial Trust List) files, as they are associated with devices rather than server names. Enabling pre8.0 compatibility mode might be necessary if you have older devices in your network that do not support FQDN for call manager names.

Ensure that after making this change, you thoroughly test your system to confirm that all endpoints can still register and communicate properly. If your documentation feels muddy, reaching out to Cisco support or consulting with a CUCM expert could provide clarity tailored to your specific setup.

[C_Noble]

Thats a good point that the certificates are based upon the hostname vs the IP address under System Server.  Thanks for the help.