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Output of : sh spantree active

Here is the output of a sh spantree active :

Why there are two different cost of 19 and 100 ?

I noticed that 100 is connected to 10 MB/ half duplex devices, where the 19 is connected to 100MB full duplex. Why ?

Any input is highly appreciated ?

Thanks

Console> (enable) sh spantree active

VLAN 1

Spanning tree enabled

Spanning tree type ieee

Designated Root 00-02-ba-86-28-00

Designated Root Priority 32768

Designated Root Cost 19

Designated Root Port 3/28

Root Max Age 20 sec Hello Time 2 sec Forward Delay 15 sec

Bridge ID MAC ADDR 00-04-dd-19-8e-00

Bridge ID Priority 32768

Bridge Max Age 20 sec Hello Time 2 sec Forward Delay 15 sec

Port Vlan Port-State Cost Prio Portfast Channel_id

------------------------ ---- ------------- --------- ---- -------- ----------

2/1 1 forwarding 19 32 disabled 0

*

*

2/40 1 forwarding 100 32 disabled 0

2/41 1 forwarding 100 32 disabled 0

2/42 1 forwarding 100 32 disabled 0

1 REPLY
Bronze

Re: Output of : sh spantree active

The value '19' is the default cost for ports running at 100Mbps.

'100' is the default cost value for 10Mbps.

The link below shows these values as well as the range of possible

values:

http://www.cisco.com/univercd/cc/td/doc/product/lan/cat6000/sw_6_3/confg_gd/spantree.htm#1157081

HTH.

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