The DHCP Lease window provides information about the local DHCP Lease when configure via DHCP is selected in the TCP/IP Control Panel. This feature is only available under MacOS 8.5 and later which includes Network Setup.
"IP Address Granted" is the IP address leased to this machine.
"Server IP Address" is the address of the DHCP Server that granted this lease.
"Lease Grant Time" shows when this lease was granted or last renewed.
"Lease Expire Time" shows when this address lease will expire.
The Refresh Data button updates the four fields above with the latest information from the Network Setup Database. Note you may need to open and close the TCP/IP control panel for new lease information to be saved to the Network Setup Database.
The Renew button sets the "Lease Grant Time" and "Lease Expire Time" to zero so the local DHCP client will try to renew the lease immediately (as needed).
When you invoke one window from another, the corresponding data is automatically transferred. Invoke the Ping window from the Window menu (Cmd-T) to ping the DHCP Server. Invoke the Trace Route window from the Window menu (Cmd-R) to begin a Trace Route to the DHCP Server that granted this lease. Invoke the Subnet Calculator (Cmd-B) to transfer the IP Address Granted to the Subnet Calculator. You can also drag and drop the IP addresses to other windows.