Creating a pending MSTP configuration

To create a pending MSTP configuration and exchange it with the active MSTP configuration:

Procedure
  1. Configure the VLANs to include in any instances in the new region. When you execute the pending command, all VLANs configured on the switch will be assigned to a single pending IST instance unless assigned to other, pending MST instances. The pending command creates the region's IST instance automatically.
  2. Configure MSTP as the spanning tree protocol, then execute write mem and reboot. The pending option is available only with MSTP enabled.
  3. Configure the pending region config-name to assign to the switch.
  4. Configure the pending config-revision number for the region name.
  5. If you want an MST instance other than the IST instance, configure the instance number and assign the appropriate VLANs (VIDs) using the pending instance1..16vlan [vid | vid-range] command.
  6. Repeat step 5 for each additional MST instance necessary.
  7. To review your pending configuration, use the show spanning-tree pending command.
  8. To exchange the currently active MSTP configuration with the pending MSTP configuration, use the spanning-tree pending apply command.