IP Helper and Bridged VLANs

[bobthecat]

Hi, our NT team has asked if we can implement DHCP on our network. They propose to use two servers (main/backup) and make use of the IP helper command on our routing modules (2*CAT5500+RSMs). I can see difficulties as we have 23 Vlans and two RSMs running HSRP between them, to add to the problem 9 of our Vlans are in the same bridge group.
1) I am concerned the both RSMs will forward the DHCP request to the same server?
2) Where the VLANs are bridged, the RSMs on each VLAN will all forward the DHCP request to the same server(if they all have IP helper configured)

I hope you can picture this, I no how hard it can be to fault from a text description.

Bob ^^

 

[scotsguy]

not sure if we have same setup but the ip helper address go under the int vlanN part of config and can be set to a variety of addresses

 

[wybnormal]

Bridged? you mean routed?

You can use IP helper to forward DHCP along with 9 other protocols or you can forward just the UDP needed for DHCP(BOOTP).. it's your option.

Set the scopes for each subnet and it works great.. we have over 50 scopes for each subnet(remotesite)

MikeS
Find me at

http://www.packetattack.com

"Diplomacy; the art of saying 'nice doggie' till you can find a rock" Wynn Catlin