If your network devices require connectivity with devices in networks for which you do not control name assignment, you can assign device names that uniquely identify your devices within the entire internetwork. The global naming scheme of the Internet, the DNS, accomplishes this task. This service is enabled by default.

To re-enable DNS if it has been disabled, use the following command in global configuration mode:

To specify one or more hosts (up to six) that can function as a name server to supply name information for the DNS, use the following command in global configuration mode:

You can specify a default domain name that the Cisco IOS software will use to complete domain name requests. You can specify either a single domain name or a list of domain names. Any IP host name that does not contain a domain name will have the domain name you specify appended to it before being added to the host table.

To specify a domain name or names, use either of the following commands in global configuration mode: