duplicate mac addresses requesting dhcp server

Gilbert Coles gilbertx07 at hotmail.com
Wed Oct 18 09:44:31 UTC 2006


First of all, thanks fior your reply. My comments are inserted below:

>> >So my question is: does the dhcp server contain logic to check the 
> >file entry assigned to mac1 before actually serving another request
> >coming from apparently the same mac1?
>You mean, can it tell the difference between a client with the real
>Mac address and another client that simply claims to have that same
>Mac address ? The answer to that is NO, it receives a packet with a
>Mac address in it, and as long as the client has correctly spoofed
>the MAC then the server can't tell.

With this question I meant that if the dhcp server has already served a mac1 
with ip1 (so there's an entry with mac1:ip1 in the dhcp.leases file) and 
another pc2 with its mac spoofed to mac1 comes along and asks the dhcp 
server for an IP, will the dhcp server (before assigning an IP to pc2) check 
in the leases file to see if it already assigned an ip to mac1?

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