dhcping

dhcping sends either a DHCPREQUEST or DHCPINFORM packet to the server and waits for an answer. Then, if a DHCPREQUEST was send, it will send a DHCPRELEASE back to the server.

This program should be installed setuid root or ran by root only, as it requires the privileges to bind itself to port 68 (bootpc). Root privileges are dropped as soon as the program has bound itself to that port.