rouge dhcp servers

[JackMajor]

is there any way to block rogue dhcp servers on your network. in particular and cable modems / routers and we had a virus spoofing as a dhcp server.

[fsebera]

Take a look at Cisco's DHCP snooping technology and Dynamic ARP inspection (DAI).

HTH

Frank

[manju.cisco]

Hi Jack,

At smiplest, you can enable ip dhcp snooping for this to work.

if you have vlan where dhcp snopping to be enable, use ip dhcp snooping vlan vlan-id

identify your port and mark them to turst, rest other ports will be untrusted by default.

interface type mod/num

ip dhcp snooping trust.

Thanks,

Manju