Setting a non-standard port for a DNS server
It is possible to specify a non-standard port number for the DNS server in the command-line interface (by default, the Domain Name System uses the standard TCP/UDP port number of 53).
Command syntax:
ip name-server {address[:port]} [{domain} [on {interface}]] For example, let's change the port number for the DNS server from 53 to 1253:
(config)>ip name-server 77.88.8.88:1253(config)>system configuration save