Configuring Multiple Spanning Tree; Configuring Mstp Properties - Cisco 220 Series Smart Plus Administration Manual

Spanning Tree Protocol

Configuring Multiple Spanning Tree

Configuring Multiple Spanning Tree
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STEP 4
Cisco 220 Series Smart Plus Switches Administration Guide Release 1.0.0.x
Multiple Spanning Tree Protocol (MSTP) is used to separate the STP port state
between various domains (on different VLANs). For example, while port A is
blocked in one STP instance due to a loop on VLAN A, the same port can be
placed in the Forwarding State in another STP instance.
To configure MSTP:
Set the STP operation mode to MSTP as described in the
Status and Global Settings
Define global MSTP parameters as described in the
Properties section.
Define MSTP instances as described in the
section. Each MSTP instance calculates and builds a loop free topology to bridge
packets from the VLANs that map to the instance.
Decide which MSTP instance be active in what VLAN, and associate these MSTP
instances to VLAN(s) accordingly as described in the
Instance section.

Configuring MSTP Properties

Use the MSTP Properties page to define the global MSTP settings. 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. MSTP allows
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 allows
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.
section.
Configuring MSTP Instance Settings
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Configuring STP
Configuring MSTP
Mapping VLANs to an MST
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