How can DHCP client get different IP address with same MAC address

Simon Hobson dhcp1 at
Wed Apr 14 07:49:34 UTC 2010

Billy Ng wrote:

>Is that any way to force the dhcp server allocate different IP 
>address to client? If the client MAC address record in the lease 
>file, and this client will get the same IP address every time.

As Glenn says, it is **REQUIRED** behaviour to give each client the 
same lease as it had last time - and the ISC server goes to some 
lengths to do this. It is possible to make clients change address 
periodically from the server end, but it requires a fair amount of 
work and all the methods I know of are horrible kludges.

If you have control of the clients, then it's possible to do it by 
getting the client to ask for some other random address.

The obvious question is ... what are you trying to achieve ?

Simon Hobson

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