CUCM FQDN

[madhav.kumar.bhardwaj12]

How to configure FQDN on CUCM PUB and SUB ? I have gone through docs and it says that just change server name from System menu of CUCM server ? I have seen issue like remote connection after doing that. So just wanted to know that is there any other setting i need to change or just server name on system menu . For subscriber FQDN  , do i need to change on PUB or Subscriber ( i assume that it need to change on PUB as server does not allow to change FQDN from SUB login) ? Correct ?

[nalonsopresidio]

Hi. There are a number of things you need to take into account. You have to have the server configured with the FQDN (verify via CLI "show network eth0" -make sure it has DNS servers and domain name info, and then "show network cluster" make sure it resolves FQDN), and also configured via web admin under the System > Server.

Before doing this, ensure all the DHCP scopes for your phones have DNS servers included that can resolve the new FQDN of the CUCM pub and sub. Also, ensure your MGCP-controlled gateways also have DNS servers and domain lookup configured.

[madhav.kumar.bhardwaj12]

Hi Nalon,

Thanks for response . To make sure that i got your answer correctly so i assume that only way to configure FQDN on CUCM is via web admin under the System > Server. Can we do through CLI ?

you are saying that --"You have to have the server configured with the FQDN" so you mean i must have correct DNS assigned while the time of installation . Correct ?

[nalonsopresidio]

SSH into your pub and run these:

"show network eth0"

"show network cluster"

Post the output here.

[madhav.kumar.bhardwaj12]

admin:show network eth0
Ethernet 0
DHCP : disabled Status : up
IP Address : X.X.X.X IP Mask : 255.255.255.000
Link Detected: yes Mode : Auto disabled, Full, 10000 Mbits/ s
Duplicate IP : no

DNS
Primary : X.X.X.X Secondary : X.X.X.X
Options : timeout:5 attempts:2
Domain : YYYY.YYYY.NET
Gateway : X.X.X.X on Ethernet 0

admin:show network cluster
X.X.X.X PUBHOSTNAME.YYYY.YYYY.NET PUBHOSTNAME Publisher callmanager DBPub authenticated
X.X.X.X SUBHOSTNAME.YYYY.YYYY.NET SUBHOSTNAME Subscriber callmanager DBSu b authenticated using TCP since Tue Jan 12 03:47:30 2016

[nalonsopresidio]

You are in good shape! All you need is to change the server from IP or A record to fqdn via webadmin System > Server. BEFORE doing this change, ensure ALL your DHCP scopes have DNS and domain info entered for all the phones currently registered, and your MGCP gateways also have DNS servers configured and domain lookup. Your MGCP gateways should also have domain name configured, so in CUCM they should appear as fqdn also.

[Alexander M Popov]

Hello,

I have the same need to add domain to the server names in system > server.

Currently they are configured with names but wouton the local domain name.

servers have domain setup and when I do show network cluster all servers uses FQDN.

Can I go in and change system > server and add the domain string without affecting anything?

Current name: cucmpublisher

Change to: cucmpublisher.domain.com

On all servers.

certificates (Tomcat is already issued using 3rd party CA and they already states issued to: cucmpublisher.domain.com

I am wanting to do this quickly and do not have time to stand up a lab, in addition, I do not wan to risk impacting users.

thanks,

-alex

[Aman Soi]

To add further, use the commands

set network dns primary x.x.x.x

set network domain abc.com which requires reboot of CUCM server.

regds,

aman

[nalonsopresidio]

Do not use any set commands yet. He is not ready at this point for that. Doing so will require cert regeneration etc which will affect the environment.