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Can we use the same VLAN for both uplink side and server side?


I have a problem regarding to the CSS configuration. In particular, I have only a VLAN to be used both for the uplink side and for server side.

I would like if there are any issues for that type of configuration.

Moreover I was thinking if I can configure the ip address inside the VLAN circuit with a narrow subnet so I can split the largest VLAN in two shortest ones.Is it correct?

Thank you very much.

Best regards.


Cisco Employee

Re: Can we use the same VLAN for both uplink side and server sid

there is no problem running with a single vlan.

You can even assign the unique vlan to 2 physical interfaces. One for uplink and for downlink.

The CSS will bridge traffic between the physical interfaces.

It's easy if you want to insert the CSS inbetween the servers and their gateway.

No need for readdressing or changing the default gateway.

If you only use 1 physical interface and 1 vlan, this is called one-armed mode, and you need to pay attention to the return traffic from server to client. This traffic must go through the CSS as well.

Client is often needed in this situation.

This is accomplished with a group command.