In this short post I will configure my router to act as a DNS server for hosts on my network.
router1#conf t
Enter configuration commands, one per line. End with CNTL/Z.
router1(config)#ip domain name lab.local
router1(config)#ip domain-lookup
router1(config)#ip name-server 8.8.8.8
router1(config)#ip dns server
The router will now pass and DNS requests to 8.8.8.8 (Google) to resolve.