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Any configuration changes made locally on the switch won't be synchronized with Sophos Central. We recommend making changes from the Sophos Central control panel instead.

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MST instance settings

Multiple Spanning Tree Protocol or MSTP lets you group multiple VLANs with the same topology requirements into one Multiple Spanning Tree Instance (MSTI). MSTP provides the capability to logically divide a Layer 2 network into regions. Every region can contain multiple instances of spanning trees. In MSTP, all interconnected bridges with the same MSTP configuration comprise an MST region.

A Common Spanning Tree (CST) interconnects all adjacent MST regions and acts as a virtual bridge node for communication between STP or RSTP nodes in the wider network. MSTP uses a single Common and Internal Spanning Tree (CIST) to connect all bridges and LAN segments. When you add the VLANs included in a MSTI, the protocol automatically builds an MSTI tree to maintain connectivity among each of the VLANs.

To add an MST instance, do as follows:

  1. Click Add.

  2. In the Add window, configure the following settings:

    Option Description
    MST ID Shows the ID of the MST group that's created. You can set a maximum of 15 groups for the switch.
    VLAN List Enter the VLAN ID range for the configured VLANs to associate with the MST ID. The VLAN ID number range is from 1 to 4094.
    Priority Select the bridge priority value. Switches running STP are each given a priority. Once BPDUs are exchanged, the switch with the lowest priority value becomes the root bridge. The default value is 32768. The range is from 0 to 61440. The bridge priority is a multiple of 4096.

Click Apply to accept the changes.