another little problem !!

I have DHCP setup on a win2k site. The lease time is 8days (default). The IP scope is 172.16.1.1/24 ti 172.16.1.254/24

Now for some reason, when I switch off one or two computers, the computers do NOT release the IP ? When I go into DHCP manager on the DHCP server, I find that even after the computer has switched off, the IP is still reserved for that computer ??

Funny enough, when I switch the computer back on, it has the same IP address that it had before I switched it off... Its as though the Server never knew that the computer was switched off ?

Does anyone know how I can get the computers to release their IP address before switching themselves off ?

ThAnKs,
ando

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DHCP clients are not like WINS clients. They do not release their IP addresses when being shut down, whereas WINS clients let the WINS server know to release the IP address associated with their registered name. A DHCP clients keeps it's assigned address when shutting down, so that upon reboot it can try to renew the lease with the DHCP server. If a DHCP server is unavailable, it will contact the default gateway to make sure it can communicate on the network. If it can communicate on the network, it continues to use the assigned IP address until it's lease expires.

If you need to make sure that clients release their IP address when being shut down, because you do not have enough addresses available, then you may try setting the lease time to a shorter period. If that isn't acceptable, then you can try to create a logoff/shutdown script that includes the ipconfig /release switch, and then import the script into a GPO.

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Absolutely correct! The DHCP will not assign a new address until the lease time is up. The computers will keep the same IP address during this period.

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ah right, thanks for that !

I'll try make a script, although this is another thing I've never done before !!

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