Root Bridge

Hi

Switch A being Server and got Spanning-tree priority 0
Switch B is client
There is dot1q trunk between Switch A and Switch B

Why do switch B indicates Root bridge for: VLAN0003

SWA# sh spanning-tree sum
Switch is in pvst mode
Root bridge for: VLAN0009, VLAN0010, VLAN0020, VLAN0030, VLAN0040-VLAN0041
Extended system ID is enabled
Portfast Default is enabled
PortFast BPDU Guard Default is disabled
Portfast BPDU Filter Default is enabled
Loopguard Default is disabled
EtherChannel misconfig guard is enabled
UplinkFast is disabled
BackboneFast is disabled
Configured Pathcost method used is short
Name Blocking Listening Learning Forwarding STP Active
---------------------- -------- --------- -------- ---------- ----------
VLAN0009 0 0 0 6 6
VLAN0010 0 0 0 6 6
VLAN0020 0 0 0 6 6
VLAN0030 0 0 0 1 1
VLAN0040 0 0 0 6 6
VLAN0041 0 0 0 6 6
---------------------- -------- --------- -------- ---------- ----------
6 vlans 0 0 0 31 31

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SWB# sh spanning-tree sum
Switch is in pvst mode
Root bridge for: VLAN0003
Extended system ID is enabled
Portfast Default is enabled
PortFast BPDU Guard Default is disabled
Portfast BPDU Filter Default is enabled
Loopguard Default is disabled
EtherChannel misconfig guard is enabled
UplinkFast is disabled
BackboneFast is disabled
Configured Pathcost method used is short
Name Blocking Listening Learning Forwarding STP Active
---------------------- -------- --------- -------- ---------- ----------
VLAN0003 1 0 0 0 1
VLAN0009 1 0 0 5 6
VLAN0010 1 0 0 5 6
VLAN0020 1 0 0 5 6
VLAN0030 1 0 0 5 6
VLAN0040 1 0 0 5 6
---------------------- -------- --------- -------- ---------- ----------
6 vlans 6 0 0 25 31

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Received on Tue Apr 12 2011 - 00:31:42 ART