Cisco CUCM using CentOS 7 DNS BIND

DNS settings on CUCM v8.6

One of the main reasons to have a local DNS server in our LAB is to be able to configure it for the Cisco Collaboration servers CUCM, UCCX, etc.

DNS is NOT mandatory for CUCM v8.6

DNS is not mandatory on Cisco Call Manager v8.6, when installing it you can perfectly decide to skip the DNS settings, see screenshot below.

DNS is not mandatory on Cisco CUCM v8.6 (it is optional – you can skip this section at will)

Only if you choose “YES” when installing CUCM and then enter DNS data you will be able to see the IP address assigned using both, the CUCM web GUI and also via the CLI.

Entering DNS settings at installation of Cisco CUCM v8.6

Checking DNS on CUCM v8.6 via GUI

CUCM v8.6 – OS Administration – show network
CUCM v8.6 – OS Administration – DNS details

Ping DNS server from CUCM GUI

CUCM OS Administration – Services – Ping
CUCM OS Administration – Services – Ping – IP Address – Ping iterations
DNS server is reacheable through ping

Checking DNS on CUCM 8.6 via CLI

You can use the following CLI command to check that DNS is working properly.

utils network host
Checking DNS from the CLI

Another useful CLI command available on CUCM v8.6 is “utils diagnose test“, this command also check Tomcat, NTP, DNS forward and reverse, HDDs and several more infrastructure related parameters, is the perfect indicator of a healthy system and proper connectivity.

utils diagnose test
CUCM v8.6 – Utils Diagnose Test

Where to go next?