Router-Name(dhcp-config)# lease 30
5) Define the Lease Duration
Router-Name(dhcp-config)# netbios-name-server 10.10.10.251
6) Define a NetBIOS WINS Server
The Default Lease time is 1 Day
Router-Name(dhcp-config)# lease 2 30
Router-Name(dhcp-config)# lease 1 6 30
30 Minutes
2 Hours and 30 Minutes
1 Day and 6 Hours and 30 Minutes
There are other optional commands, visit the Cisco DHCP Configuration Guide to see them