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how to block dhcp from my client to me!!

Posted: Thu Mar 13, 2008 10:58 am
by trottolino1970
how to block dhcp from my client to me and Sharing files and folders?

Re: how to block dhcp from my client to me!!

Posted: Fri Mar 14, 2008 10:52 pm
by sandov63
built this rule under ip -> firewall -->> filter rules

add chain=forward action=drop dst-port=68 protocol=udp comment="DROP DHCP \
SERVERS" disabled=no
add chain=input action=drop dst-port=68 protocol=udp comment="" disabled=no

this way you are blocking broadcasting from port 68 of users whose wake up a dhcp server

Re: how to block dhcp from my client to me!!

Posted: Sat Mar 15, 2008 2:00 am
by Chupaka
are broadcast packets affected by forward chain? :)

Re: how to block dhcp from my client to me!!

Posted: Sat Mar 15, 2008 9:05 am
by trottolino1970
are broadcast packets affected by forward chain? :)
And how to block them?

Re: how to block dhcp from my client to me!!

Posted: Thu Mar 20, 2008 10:35 pm
by nickb
Turn off "forwarding" on the wireless side; such as disable "default forward" if you have are using "default authenticate", or uncheck "Forwarding" in the access list entry for a MAC address. This will prevent DHCP from broadcasting to other wireless clients.

Re: how to block dhcp from my client to me!!

Posted: Fri Mar 21, 2008 1:09 am
by tenis
Turn off "forwarding" on the wireless side; such as disable "default forward" if you have are using "default authenticate", or uncheck "Forwarding" in the access list entry for a MAC address. This will prevent DHCP from broadcasting to other wireless clients.
What exactly turning off default-forwarding do? It just stops broadcasting all broadcasts from clients? This would be great, cause I had quite a few issues related to this (private DHCP server on client side, providing incorrect leases, etc.)
But I still would like to have clients able to speak between each other. How the arp who-has will be responded if it will not be broadcasted to all clients. Would AP be able to make this working?

Re: how to block dhcp from my client to me!!

Posted: Fri Mar 21, 2008 4:28 am
by gmeyer
Add filters in the bridge on the wireless interface

add chain=input mac-protocol=ip src-port=67 ip-protocol=udp action=drop comment="Drop DHCP" disabled=no in-interface=wireless

add chain=forward mac-protocol=ip src-port=67 ip-protocol=udp action=drop comment="Drop DHCP" disabled=no in-interface=wireless

Remember that broadcast working on layer 2

Re: how to block dhcp from my client to me!!

Posted: Tue Mar 25, 2008 2:18 pm
by totalnett
Can't get this to work.
I have routeros 3.4 on a RB192...

Do i have to mark packets in Mangle first? How should i do this?