Reference Guide

660 | Multiple Spanning Tree Protocol (MSTP)
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FTOS supports three other variations of Spanning Tree, as shown in Table 44.
Implementation Information
The FTOS MSTP implementation is based on IEEE 802.1Q-2003, and interoperates only with bridges
that also use this standard implementation.
MSTP is compatible with STP and RSTP.
FTOS supports only one MSTP region.
When you enable MSTP, all ports in Layer 2 mode participate in MSTP.
On the C-Series and S-Series, you can configure 64 MSTIs including the default instance 0 (CIST).
Configure Multiple Spanning Tree Protocol
Configuring Multiple Spanning Tree is a four-step process:
1. Configure interfaces for Layer 2. See page 946.
2. Place the interfaces in VLANs.
3. Enable Multiple Spanning Tree Protocol. See page 661.
4. Create Multiple Spanning Tree Instances, and map VLANs to them. See page 662.
Related Configuration Tasks
Create Multiple Spanning Tree Instances on page 662
Add and Remove Interfaces on page 661
Influence MSTP Root Selection on page 663
Interoperate with Non-FTOS Bridges on page 663
Modify Global Parameters on page 664
Modify Interface Parameters on page 665
Configure an EdgePort on page 666
Flush MAC Addresses after a Topology Change on page 667
Debugging and Verifying MSTP Configuration on page 672
Table 31-1. FTOS Supported Spanning Tree Protocols
Dell Force10 Term IEEE Specification
Spanning Tree Protocol 802.1d
Rapid Spanning Tree Protocol 802.1w
Multiple Spanning Tree Protocol 802.1s
Per-VLAN Spanning Tree Plus Third Party