How can I forbid access to customer that force their IP to static ...
dhcp1 at thehobsons.co.uk
Sat Jul 7 07:15:05 UTC 2007
Sébastien CRAMATTE wrote:
>How can I forbid access to customer that force their IP to static ...
>Some customers change their windows property and force the IP as
>be a static one ...
>I would like to prevent this ...
>Does it exists a feature inside dhcpd to do this ?
You cannot do this with DHCP.
You will have to find/write some software that will do it outside of DHCP.
I vaguely recall a description from someone on
this list some time ago of the setup they used :
Software interrogates DHCP for leases - you can
read the leases file, or the "on commit" function
may be useful. This might have been combined with
a registration system, I can't recall now (try
looking at Netreg and see what that does).
Once you have a list of addresses that SHOULD be
in use, you can compare the traffic seen on the
network with this list and flag up any rogue IPs.
Using SNMP (or whatever you prefer), you can
track down which switch port the device is
connected to, turn it off, send alert to admins,
You possibly want to be monitoring what port(s) a
device is connected to anyway in a public network
so that you have an audit trail of "who was
where" if you get complaints about one of your
customers - the "one of your customers at a.b.c.d
( is | was ) ( port scanning me | brute force
pass attacking me | DOSing me | killing my DNS
server with queries | whatever)" type complaints.
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