3800 routing challenge

[ArjanA]

Hi,

I have a network with multiple gateways on each VLAN.

There is a 3800 and a Cisco ASA that both act as router.

The 3800 has IP address 10.x.y.254 in each VLAN.

The ASA has IP address 10.x.y.249 in each VLAN.

The current setup is to route all interVLAN traffic on the 3800 and all internet traffic to the Cisco ASA.

This requires setting static routes or defining dhcp option 121 (classless static route) for all hosts.

I would like to have the 3800 as default gateway for all hosts in each VLAN.

Can I use policy based routing on the 3800 to disable the need for static routes?

Or should I reconfigure the 3800 and the ASA and use a routing subnet?

Kind regards,

Arjan

[paulgear]

Hi Arjan,

In my opinion, the simplest option is to put the ASA behind the 3800 and have all clients use the 3800 as the default gateway.

That said, when i researched DHCP option 121, i found that the support for it was inconsistent across Windows versions, and i wasn't prepared to put time into it with the possibility of it not working. If DHCP option 121 works for you, then using it makes good sense. For routing between the ASA and 3800 in this case, i would recommend using a dynamic routing protocol such as OSPF (preferably) or RIP (if you must).