purpose of "hostname" and "domain-name"

m4rtin

It's elementary to configure a hostname and domain-name for a router or switch:

Router#conf t
Enter configuration commands, one per line.  End with CNTL/Z.
Router(config)#hostname R1
R1(config)#ip domain-name example.org
R1(config)#end
R1#

However, what is the use of "hostname" and "domain-name". Hostname is useful for identifying the device(on the CLI or for example over CDP), both "hostname" and "domain-name" are used for identifying host SSH public key, but what else? Could somebody name additional uses for domain-name in IOS?

DPG

It is used for the search domain when you do local DNS lookups.

phoeneous

DNS is your friend.

m4rtin

DPG wrote: »

It is used for the search domain when you do local DNS lookups.

By "local DNS lookups" you mean the ones which are done from the router/switch? However, what if I have specified "ip domain-list example.org"? According to Configuring DNS on Cisco Routers  [IP Application Services] - Cisco Systems the default domain name is not used in that case. Are there any other use for "ip domain-name"?

gorebrush

Hostname is important for generation of certificates as well.

m4rtin

gorebrush wrote: »

Hostname is important for generation of certificates as well.

yes, but not if you specify label during the creation of the key.