By default, the spanning tree protocol STP is enabled on all of the interfaces of the BIG-IP® system. The default spanning tree configuration includes a single spanning tree instance, named 0. A spanning tree instance is a discrete spanning tree for a network. While STP and RSTP allow only one spanning tree instance (instance 0), MSTP allows you to create multiple spanning tree instances, to manage redundant paths for specific VLANs on the network.
When running MSTP, instances that you create have instance members. An instance member is a VLAN that you assign to an instance when you create that instance. You can assign as many or as few members to an instance as you deem necessary. By default, all VLANs on the BIG-IP system are members of instance 0.
If you create an instance and attempt to add a VLAN that is already a member of another instance, the BIG-IP system deletes the VLAN from the existing instance and adds the VLAN to the new instance.
Each instance name must be a numeric value that you assign when you create the instance.
Only users with either the Administrator or Resource Administrator role can manage spanning tree instances.