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Spanning Tree
MSTP Properties
Cisco 350XG & 550XG Series 10G Stackable Managed Switches
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MSTP Properties
The global MSTP configures a separate Spanning Tree for each VLAN group and
blocks all but one of the possible alternate paths within each spanning tree
instance. MSTP enables formation of MST regions that can run multiple MST
instances (MSTI). Multiple regions and other STP bridges are interconnected using
one single common spanning tree (CST).
MSTP is fully compatible with RSTP bridges, in that an MSTP BPDU can be
interpreted by an RSTP bridge as an RSTP BPDU. This not only enables
compatibility with RSTP bridges without configuration changes, but also causes
any RSTP bridges outside of an MSTP region to see the region as a single RSTP
bridge, regardless of the number of MSTP bridges inside the region itself.
For two or more switches to be in the same MST region, they must have the same
VLANs to MST instance mapping, the same configuration revision number, and the
same region name.
Switches intended to be in the same MST region are never separated by switches
from another MST region. If they are separated, the region becomes two separate
regions.
This mapping can be done in the
page.
Use this page if the system operates in MSTP mode.
To define MSTP:
STEP 1
Click
Spanning Tree
>
STP Status and Global Settings
.
STEP 2
Enable MSTP.
STEP 3
Click
Spanning Tree
>
MSTP
Properties
.
STEP 4
Enter the parameters.
•
Region Name
—Define an MSTP region name.
•
Revision
—Define an unsigned 16-bit number that identifies the revision of
the current MST configuration. The field range is from 0 to 65535.