DHCP spoofing and Cisco switched network.

[johnleeee]

Hi all,

Id like to discus one issue related to DHCP spoofing.

We have all over our network Cisco

switches with one L3 switch moving DHCP requests from one

network to other network where

is our DHCP server. So we have

configured ip helper-address on interface.

But when someone plug into client?s network DHCP server than

clients will take the IP addresses from this server.

So my question is, how to configure Cisco switches or LAN not to be harmful with other DHCP

server pluged on network? But still request IP addresses from only one DHCP server.

BR

jl

[kyawzawhtut]

Hi John

You can implement DHCP Snooping to prevent workstations from running their own dhcp server. You can check detail by just searching this term "dhcp snooping".

HTH.

Plz rate if helpful to u.

Cheers

Joe

[johnleeee]

Hi Joe,

thanks..we have some C2924XL switches too.

Is it possible to configure this on such kind

of switch?

Is it possible resolve DHCP spoofing the other way?

BR

jl

[kyawzawhtut]

Hi John

According to feature navigator tool, feature is not supported in C2924XL.

According to my knowledge, it is the only way to prevent dhcp spoofing.

HTH.

And plz don't forget to put in some coins to fortune teller machine. ^.^

Cheers

Joe