2 DHCP + VSS

[ahmad1982]

Hi,

i have scenario with two 4500 - core, with vss configuration.

though it will be one core " logically ", but can i have dhcp on both with same pool  ? in case if one of them or VSL went down for any reason!

R,

AM

[Philip D'Ath]

Well they share the same config, so inherently yes.

If you configure DHCP, and one 4500 fails over, the other will take over.

[ahmad1982]

Hi,

Yes you correct Philip, i want to run the DHCP on both 4500x.

Ill try then and see.

thanks

A

[paul driver]

Hello

no you cannot - once you enable vss the configuration is basically wiped so any configuration including dhcp applied after vss is enabled will be applied logically on the two physical switches has one device

Res

paul

[ahmad1982]

from the fact that we will have one control plane (with VSS), yes its not possible.

but is it the same with data plane ?

[pwwiddicombe]

What are you using for DHCP services?  Some DHCP services can provide an "intelligent backed up DHCP service" where a scope is defined and replicated to servers; and others do not. 

I don't believe Microsoft's DHCP will like sharing the same address pools; although what you CAN do is to define the same scope on both, but exclude half of the addresses that will be used on the OTHER DHCP server (and vice versa); so both DHCP servers won't hand out the same addresses...

[Philip D'Ath]

I think @ahmad1982 was referring to running DHCP on the 4500's themselves.