Configuring A Bridge - Motorola RFS Series Reference Manual

• Common and Internal Spanning Trees (CIST) – CIST contains all of the ISTs and bridges not formally
configured into a region. This instance interoperates with bridges running legacy STP and RSTP
implementations.
• Multiple Spanning Tree Instance (MSTI) – The MSTI is identified by an MSTP identifier (MSTPid) value
from 1 to 15. This defines an individual instance of a spanning tree. One or more VLANs can be assigned
to an MSTI. A VLAN cannot be assigned to multiple MSTIs. The multiple spanning tree instance 0 is
always present. VLANs not explicitly assigned to an instance are assigned to instance 0.
• MSTP Region – These are clusters of bridges that run multiple instances of the MSTP protocol. Multiple
bridges detect they are in the same region by exchanging their configuration digest (which is dependent
on the VLAN to instance mapping), region name and revision-level. If you need to have two bridges in the
same region, the two bridges must have identical VLAN to instance mappings, region names and
revision-levels.
To configure the switch for MSTP support, configure the region name and the revision on each switch being
configured. This region name is unique to each region. Then create one or more instances and assign IDs.
VLANs are then assigned to instances. These instances must be configured on switches that interoperate
with the same VLAN assignments. Port cost, priority and global parameters can then be configured for
individual ports and instances.
The Multiple Spanning Tree option contains separate tabs for the following activities:
•

Configuring a Bridge

• Viewing and Configuring Bridge Instance Details
• Configuring a Port
• Viewing and Configuring Port Instance Details
4.10.1 Configuring a Bridge
Use the Bridge tab to configure the Bridge. This window displays bridge configuration details for the switch
To configure the MSTP bridge:.
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Network Setup