Change Server Name from IP to FQDN

[refram]

I just need to change the names of the servers in a CUCM cluster (in System > Server) from the IP to the FQDN of the server.  I do not need to change the hostname, I do not need to change the IP.  I'm using CUCM 10.5.1.  We are running in mixed mode with phones that have secure profiles on them.  DNS is very stable in our environment.  Our issue is one of certificates, so we need to make this change.

I've been looking at other posts and there seem to be two camps, one is that I need to follow detailed directions that were laid out for changing the hostname of the server...which I'm not really doing, and the other is to just go ahead and change the name from the IP to an FQDN and it will be fine.  No need to go into the CLI or even restart anything.  Has anyone had successes or epic failures using one method or the other?

[George Thomas · Accepted solution]

I just did this recently on a 10.5.2 cluster which is running in mixed mode. Changing the System > Server from IP to FQDN doesnt regenerate any certificates. It just changes how the phones reference. I didnt have in any issues with this change FWIW. 

[refram]

I went ahead and did it.  I did, in fact check and recheck DNS, and I did one at a time.  When it was all done, I also restarted the CUCM and CUPS servers just to make sure that nothing went haywire down the road.  No problems with servers, no problems with phones.  It might be important to emphasize that I am in Mixed Mode and I've read that if you aren't you might have some issues with phones not having the new server names in their trusted list.  I can't confirm this, though.

[Ala Raed Issa]

Hi Refram,

Did you change IP address to FQDN to all servers from the publisher, then you restarted all servers in one time? in other words, should we restart the cluster after changing IP-to-FQDN for every server? or it is one time restart ?

Please detail the procedures which you follow

[refram]

I changed the name on the Publisher first.  Then I changed the names on each Subscriber.  After changing the names on every server I checked dbreplication to make sure that the name was synchronized.  Then I rebooted the Publisher and when I came up I rebooted the Subscribers.  We have a full load of Subscribers so I restarted several Subs at the same time with the idea that I did NOT restart Subs to which the people registered to the fist set of Subs would fail over.

[Gerson Fabian Morales Marin]

Check this:

Link= https://supportforums.cisco.com/document/12927561/how-change-your-call-manager-server-ip-use-fqdn

[Gordon Ross · Accepted solution]

I did this a while ago on our cluster.

Before you start, make sure the phones are getting DNS server details from their DHCP Servers.  Also check that the CUCM servers have DNS configured too.

Then check, double check and triple check that the phone & CUCM DNS servers can resolve the intended FQDN of the CUCM server(s).

When you come to change the CUCM server name from IP to FQDN.

1 - Do one server at a time.

2 - When setting the name: Check, double check and triple check you've entered the name correctly *BEFORE* you press return/submit.

GTG

[dsobrinho]

Hi

I have the same doubt about difference between "Server Name in gui" and "Hostname in cli".

When I included the CUCM cluster in DNS can I create a different name from hostname to CUCM servers name?

Ex: the server name is based in IP Address 10.10.20.5 Pub and 10.10.20.6 Sub.

In the CLI with show status command the hostname is CCMACME-PUB and CCMACME-SUB. I need use the same name from hostname to apply to server name? It is confusing.

Best regards,

Daniel

[AmmarMalhotra8566]

we have CUCM 10.5.1, 

with Name SEPCO-CUCM-PUB, no DNS and no domain 

if i change will it cause Certificate and license issues. 

[Maren Mahoney]

Ammar,

Yes it will. The other thread you and I are working on will address the phone registration issues without changing the hostname, domain, FQDN or anything else on your CUCM server. If, after we get your phones registered, you would like to change these things on your CUCM server we should start a new thread about that.

Maren