[c-nsp] Performace - IP DHCP Snooping

[Andrew Miehs]

Hi all,

Does anyone know whether/ and how much of a performance issue DHCP Snooping can cause to layer 2 switches such as the 3560s, 2960Ss and 3750s?

I have about 400 access switches that I want to reconfigure, but am a little worried about nasty side effects which take 2 weeks to get noticed. I would also like to use "ip dhcp snooping vlan 1 4096" so that I don't need to check each switch individually as to which vlans are actually in use.

Thankfully we only have 6 DHCP servers, and none of them are on these access switches, so I only need work out which for each of these switches which port is the uplink. Am planning on using ruby/ ssh and
   show run | i default gateway
   show mac address-table | i <%ip of gateway%>
and use the interface listed as the trusted uplink/ port-channel, or gigabit…


Thanks for any tips.

Regards