This section explains how to configure units. Units do not necessarily have to be preconfigured in order to be added to the stack.

General information: All configurations on the stack, except unit numbers, are stored on the management unit. This means that a stack unit may be replaced with another device of the same type without having to reconfigure the switch. Unit numbers are stored independently on each switch, so that after power cycling the stack, the units always come back with the same unit numbers. The unit type associated with each unit number may be learned by the management unit automatically as the units are connected or preconfigured by the administrator.

  1. Issue the command member unit-id switchindex to preconfigure a unit from the config stack mode. Supported unit types are shown by the show supported switchtype command.
    • To display supported switches, use Privileged EXEC mode. Enter the command show supported switchtype SID.
    • To add a new member (see Adding a Unit to an Operating Stack), use Config stack mode. Enter the command member unit-id.
  2. Next, configure the unit you just defined with configuration commands, just as if the unit were physically present.
  3. Ports for the preconfigured unit come up in "detached" state and can be seen with the show port all command in Privileged EXEC mode. The detached ports may now be configured for VLAN membership and any other port-specific configuration.
  4. After a unit type is preconfigured for a specific unit number, attaching a unit with a different unit type for this unit number causes the switch to report an error. The Privileged Exec mode show switch command indicates "config mismatch" for the new unit and the ports on that unit do not come up. To resolve this situation, you may change the unit number of the mismatched unit, using the procedure in Renumbering Stack Members, or delete the preconfigured unit type using the command no member unit-id from the config stack mode.