Configuring Network Services for the CCENT Certification Exam

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>enable
NY-R1#config term
NY-R1(config)#ip host BOS-R1 24.0.0.2

To verify that the entry has been added:

NY-R1(config)#exit
NY-R1#show hosts

The following commands enable DNS lookups and specify the DNS server of 23.0.0.200 to send DNS queries to. The domain name is also set to gleneclarke.com.

NY-R1>enable
NY-R1#config term
NY-R1(config)#ip domain-lookup
NY-R1(config)#ip name-server 23.0.0.200
NY-R1(config)#ip domain-name gleneclarke.com

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)#network 23.0.0.0 255.0.0.0
NY-R1(dhcp-config)#default-router 23.0.0.1
NY-R1(dhcp-config)#dns-server 23.0.0.200
NY-R1(dhcp-config)#lease 7 0 0
NY-R1(dhcp-config)#exit
NY-R1(config)#ip dhcp excluded-address 23.0.0.1 23.0.0.15

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 10.0.0.0 0.255.255.255
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