Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. And see here for current known issues.

New Member

IOS DHCP Server - Possible to restrict to phones only?

I've got a handful of new 891 remote office routers that I've configured to

connect via two concurrent GRE/IPSec tunnels back to two different home offices.

One home office provides data for the PCs, and the second home office provides voice for Cisco phones.

I've got the 4-port switch in the 891 router partitioned into two VLANS, one for voice-only, the other for data-only.

Each VLAN gets routed back to the appropriate home office via its own GRE/IPSec tunnel.

I've got a dhcp enabled in each 891 to provide address and option 150 service for Cisco phones at the remote offices and everything is working OK except when a user at the remote office plugs a PC into one of the PoE phone ports on the 891, and the dhcp server doles out an address to the PC and then the user can try to prowl around on my voice network, which I need to stop.

Is there a simple way which I can comfigure the local dhcp service running in IOS on the 891 only respond for Cisco phones only, and simply not give out any address to any other non-phone device ?

New Member

Re: IOS DHCP Server - Possible to restrict to phones only?

I think you might want to look at 802.1x protocol. I think by now cisco phones support 802.1x. So you would controll it based on if they have access to the voice vlan they would get access to the voice dhcp server. Computers that fail would be send to guest vlan that could only have internet access or data access.

hope that help a little.


CreatePlease login to create content