MSTP (Multiple Spanning Tree Protocol) uses the MSTI (Multiple Spanning Tree Instances) ID, not an Stpd ID, to identify the spanning tree contained within the region. As previously described, the MSTI ID only has significance within its local region, so you can re-use IDs across regions.
To configure the MSTI that is inside an MSTP region and its associated MSTI ID, use the following command and specify the mstp [msti instance] parameters:
configure stpd stpd_name mode [dot1d | dot1w | mstp [cist | msti instance]]The range of the MSTI instance ID is 1–4094.