Enhancements in Release F.04.08

Configuring Rapid Reconfiguration Spanning Tree (RSTP)

Syntax:

Abbreviations:

spanning-tree [ethernet] <port-list>span <port-list>
path-cost <1 - 200000000>path <1 - 200000000>
point-to-point-mac <force-true force-false auto>

forc <force-t force-f auto>

priority <0 - 15>

pri <0 - 15>

[no] spanning-tree [ethernet] <port-list>[no] span <port-list>

edge-port

edge
mcheckmch

Defaults: see the table on the previous page.

 

Note on Path Cost

RSTP implements a greater range of path costs and new default path cost values to account for higher network speeds. These values are different than the values defined by 802.1D STP as shown in the next table.

Port Type

802.1D STP Path Cost

RSTP Path Cost

10 Mbps

100

2 000 000

100 Mbps

10

200 000

1 Gbps

5

20 000

10 Gbps

?

2000

 

 

 

Because the maximum value for the path cost allowed by 802.1D STP is 65535, devices running that version of Spanning Tree cannot be configured to match the values defined by RSTP, at least for 10 Mbps and 100 Mbps ports. In LANs where there is a mix of devices running 802.1D STP and RSTP, you should reconfigure the devices so the path costs match for ports with the same network speeds.

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