Port speed

The 2930 switches support only one port speed across all VSF ports in the stack. This port speed is configurable, and is initially set automatically to the highest speed capable by the first VSF port that is configured.

Users can add ports of any speed to a VSF link. Only ports which match the configured VSF port speed will link up in the VSF stack. Ports which do not match the VSF port speed will be in an error state, stating port speed mismatch. This new feature allows users to migrate a stack based on 1G interconnects to a stack based on 10G interconnects, and vice-versa, without having to reform the VSF stack from the beginning. The migration procedure from 1G interconnects to 10G interconnects is:

In a stack with 1G interconnects, the user simply adds the 10G ports to each link. These ports should also be physically interconnected, but they will not link up. Once all the configuration is complete and the interconnections are made, the user changes the port speed using the command vsf port-speed 10g. This triggers a reboot of the stack, and once the stack is reformed, it uses the configured 10G ports while the 1G ports will be in error state. The 1G ports can now be disconnected and unconfigured.