Separate L3 switch in two ???

[netadmincsm]

Hi All

I have a Cisco Layer 3 switch.

Actually all packets comming from subnet 1, 2 and 3 are going directly to subnet 10, 11, 12 without going into my firewall because all destination subnet are directly connected

I would want packets comming from subnet 1, 2 or 3 go through Firewall into the outside interface then get out of it from the inside interface untill they reach their destination subnet 10, 11 or 12.

How can this be done ?

See attached file for detail.

Thank you very much.

[Amit Aneja · Accepted solution]

This can be done by doing policy based routing.

sample config for One vlan:

access-list 100 permit ip x.x.1.0 0.0.0.255 x.x.10.0 0.0.0.255

access-list 100 permit ip x.x.1.0 0.0.0.255 x.x.11.0 0.0.0.255

access-list 100 permit ip x.x.1.0 0.0.0.255 x.x.12.0 0.0.0.255

route-map TO_FIREWALL_OUT

match ip address 100

set ip next hop

int vlan 1

ip policy route-map TO_FIREWALL_OUT

You would need to do changes in Firewall as well so that this traffic is permitted on outside interface.

HTH,

If helpful, Rate

[netadmincsm]

Can I rate this extremely usefull

Thank you very much.

It's working very well

[Joseph W. Doherty]

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Another option would be, if supported by your L3 switch, to use VRFs to have two different routing instances.  Then your two sets of subnets would not be directly visible to each other.