Reference Guide

588 | 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.
2. Place the interfaces in VLANs.
3. Enable Multiple Spanning Tree Protocol.
4. Create Multiple Spanning Tree Instances, and map VLANs to them.
Related Configuration Tasks
• Create Multiple Spanning Tree Instances on page 589
• Add and Remove Interfaces on page 589
• Influence MSTP Root Selection on page 591
• Interoperate with Non-FTOS Bridges on page 591
• Modify Global Parameters on page 592
• Modify Interface Parameters on page 593
• Configure an EdgePort on page 594
• Flush MAC Addresses after a Topology Change on page 595
• Debugging and Verifying MSTP Configuration on page 599
Table 27-1. FTOS Supported Spanning Tree Protocols
Dell Force10Term 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