Q on Sup-720-3B with 6509E

[sanjaynadarajah]

Hi,

My question is that I have a Sup720-3B on a 6509E and have created 3 interface vlan. Can routing work between these interface vlan wihtout enabling routing in it ?

Example, if I have created three interface vlan, which are vlan 10,20 and 30. Can L3 switching move packets from vlan 20 to vlan 30 without enabling any routing protocol ?

Pls advice ...

Thank you,

- sn -

[Jon Marshall · Accepted solution]

Hi

The switch would need to have ip routing enabled but you would not need to run a routing protocol such as OSPF, EIGRP etc. if all you wanted to do was route between these 3 vlans.

Hope i've understood the question

Jon

[sanjaynadarajah]

Hi Jon,

Yes that was my question. So what is taking place is L3 switching right, switching is happening based on IP address ?

Pls advice,

Thank you,

[Jon Marshall · Accepted solution]

Hi

If you are going from a client in one of your vlans to a client in another of your vlans then yes you are switching at layer 3. So the packet will be forwarded from the client to it's default gateway based on the fact that the layer 3 IP address is on a different subnet.

If you are going from a client in one vlan to another client in the same vlan then you are switching at layer 2.

Layer 3 switching is just terminology for routing in hardware rather than in software.

HTH

Jon