Reference Guide

632 | Multiple Spanning Tree Protocol (MSTP)
www.dell.com | support.dell.com
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 930.
2. Place the interfaces in VLANs.
3. Enable Multiple Spanning Tree Protocol. See page 633.
4. Create Multiple Spanning Tree Instances, and map VLANs to them. See page 634.
Related Configuration Tasks
Create Multiple Spanning Tree Instances on page 634
Add and Remove Interfaces on page 633
Influence MSTP Root Selection on page 635
Interoperate with Non-FTOS Bridges on page 635
Modify Global Parameters on page 636
Modify Interface Parameters on page 637
Configure an EdgePort on page 638
Flush MAC Addresses after a Topology Change on page 639
Debugging and Verifying MSTP Configuration on page 644
Table 30-74. 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