This section reviews popular commands used when configuring a Cisco device for name resolution, DHCP services, and NAT. You'll need to know these for the CCENT Certification exam.

The following commands configure the hostname table on a router and display the entries in the hostname table:

NY-R1#config term
NY-R1(config)#ip host BOS-R1

To verify that the entry has been added:

NY-R1#show hosts

The following commands enable DNS lookups and specify the DNS server of to send DNS queries to. The domain name is also set to

NY-R1#config term
NY-R1(config)#ip domain-lookup
NY-R1(config)#ip name-server
NY-R1(config)#ip domain-name

The following commands configure your router as a DHCP server by setting an address pool (range of addresses to give out) and setting up excluded addresses that are not to be given out. The lease time is set to 7 days in this example.

NY-R1(config)#ip dhcp pool NY_Network
NY-R1(dhcp-config)#lease 7 0 0
NY-R1(config)#ip dhcp excluded-address

The following commands configure NAT overload services on a router called NY-R1. In this example, a list of source addresses is created in access list #1, which is then used as the inside source list. The FastEthernet 0/0 port is the overloaded public address port that all inside addresses get translated to.

NY-R1(config)#Access-list 1 permit
NY-R1(config)#ip nat inside source list 1 interface 
     FastEthernet 0/0 overload
NY-R1(config)#interface FastEthernet0/0
NY-R1(config-if)#ip nat outside
NY-R1(config-if)#interface FastEthernet0/1
NY-R1(config-if)#ip nat inside