DHCP lease can be either terminated by user or network administrator, or it may expire. Lease termination may be forced when the DHCP server is changed.
On Windows termination is done from Command Prompt by using “ipconfig /release” command. This command will erase all the IP, gateway, and subnet mask data from TCP/IP configuration file.
In order to request new IP data, the “ipconfig /renew” command should be used. The renewing command might fail sometimes if:
client disconnected from the network
cable is unplugged or faulty
DHCP server is offline
DHCP server is configured improperly
client protocols are not installed or configure properly
Figure 1. Example of release and renew functions execution.
