It is possible to define static hostname-to-address mappings on a Cisco device for the purpose of name resolution. This is usually done in environments without a DNS server.
The mappings can be defined using the global configuration command ip host HOSTNAME IP_ADDRESS:
Floor1(config)#ip host HQ_SERVER 192.168.0.100
In the output above we’ve defined the IP address of 192.168.0.100 for the hostname HQ_SERVER. To display the hostname-to-address mappings, the show hosts command is used:
Floor1#show hosts Default Domain is not set Name/address lookup uses domain service Name servers are 255.255.255.255 Codes: UN - unknown, EX - expired, OK - OK, ?? - revalidate temp - temporary, perm - permanent NA - Not Applicable None - Not defined Host Port Flags Age Type Address(es) HQ_SERVER None (perm, OK) 0 IP 192.168.0.100
We can ping the server using its hostname to verify that the hostnames are being resolved:
Floor1#ping HQ_SERVER Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 192.168.0.100, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 0/0/1 ms
You can see that HQ_SERVER responded to the ping request, which means that the name resolution was successful.
Download our Free CCNA Study Guide PDF for complete notes on all the CCNA 200-301 exam topics in one book.
We recommend the Cisco CCNA Gold Bootcamp as your main CCNA training course. It’s the highest rated Cisco course online with an average rating of 4.8 from over 30,000 public reviews and is the gold standard in CCNA training: