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Here, you can set the hostname, MOTD banner, and enable secret password. Last, I clicked on the DHCP folder, then the DHCP pool icon. I then clicked Add and created a DHCP pool on my router. Now, let’s take a look at the configuration on the router: Todd#sh run Building configuration... [output cut] hostname Todd ! ip domain name lammle.com [output cut] ip dhcp excluded-address 172.16.10.1 ip dhcp excluded-address 172.16.10.11 172.16.10.254 ! ip dhcp pool Todd's_LAN import all network 172.16.10.0 255.255.255.0 !
Using DNS to Resolve Names If you have a lot of devices and don’t want to create a host table in each device, you can use a DNS server to resolve hostnames. Any time a Cisco device receives a command it doesn’t understand, it will try to resolve it through DNS by default. Watch what happens when I type the special command todd at a Cisco router prompt: Corp#todd Translating "todd"...domain server (255.255.255.255) Translating "todd"...domain server (255.255.255.255) Translating "todd"...domain server (255.255.255.255) % Unknown command or computer name, or unable to find computer address Corp#
It doesn’t know my name or what command I am trying to type, so it tries to resolve this through DNS. This is really annoying for two reasons: first, because it doesn’t know my name, and second, because I need to hang out and wait for the name lookup to time out. You can get around this and prevent a time-consuming DNS lookup by using the no ip domain-lookup command on your router from global configuration mode.