Document No. 10-300077, Issue 2 7-19
Configuring Rapid Spanning Tree
Operational Path
Cost The path cost that Spanning Tree is using for the port:
• If Administrative Path Cost is set to a nonzero
value, this field displays that nonzero value.
• If Administrative Path Cost is set to 0, the switch
is running Rapid Spanning Tree, and Path Cost
Default for the bridge is set to Rapid-spanning-
tree, then this field displays the following values
(recommended in Table 17-7 of IEEE Std. 802.1w-
2001).
— 10 Mbps port—2,000,000
— 100 Mbps port—200,000
— 1 Gbps port—20,000
— 10 Gbps port—2,500
For hunt groups, this field displays the operational
path cost of one link divided by the number of
links in the hunt group. For example, if a hunt
group comprises four 1-GB ports, and the
operational path cost for one port is 20,000, the
operational path cost for the hunt group is 5,000
(20,000 ÷ 4).
• If Administrative Path Cost is set to 0 and the
switch is running common Spanning Tree, then this
field displays the following values (regardless of
the Path Cost Default setting):
— For 10 MB ports, 100
— For 100 MB ports, 19
— For 1 GB ports, 4
— For 10 GB ports, 3
Note: If the port is a trunk port (IEEE 802.1q or
Multi-Layer tagging is enabled), the operational path
cost is one less than the value in the preceding list.
For hunt groups, this field displays the operational
path cost of one link minus 1. For example, if a
hunt group comprises four 1-GB ports, and the
operational path cost for one port is four, the
operational path cost of the hunt group is 3 (4 – 1).
Table 7-5. Spanning Tree Port ConfigurationField Definition
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