Hi guys,
I was facing today a strange behavior on a 3560 running 12.2(35)SE5, basically it doesn't send BPDU out of the interface.
Here is the detailed output of spanning-tree and interface configuration.
show spanning-tree interface fa0/1 det
Port 3 (FastEthernet0/1) of VLAN0001 is root forwarding
Port path cost 19, Port priority 128, Port Identifier 128.3.
Designated root has priority 20481, address 2c54.2d02.e300
Designated bridge has priority 20481, address 2c54.2d02.e300
Designated port id is 128.30, designated path cost 0
Timers: message age 15, forward delay 0, hold 0
Number of transitions to forwarding state: 2
Link type is point-to-point by default, Peer is STP
Loop guard is enabled by default on the port
BPDU: sent 7, received 10163
Port 3 (FastEthernet0/1) of VLAN0008 is root forwarding
Port path cost 19, Port priority 128, Port Identifier 128.3.
Designated root has priority 24584, address 2c54.2d02.b440
Designated bridge has priority 24584, address 2c54.2d02.e300
Designated port id is 128.30, designated path cost 4
Timers: message age 16, forward delay 0, hold 0
Number of transitions to forwarding state: 2
Link type is point-to-point by default, Peer is STP
Loop guard is enabled by default on the port
BPDU: sent 7, received 10156
Port 3 (FastEthernet0/1) of VLAN0010 is root forwarding
Port path cost 19, Port priority 128, Port Identifier 128.3.
Designated root has priority 20490, address 2c54.2d02.e300
Designated bridge has priority 20490, address 2c54.2d02.e300
Designated port id is 128.30, designated path cost 0
Timers: message age 16, forward delay 0, hold 0
Number of transitions to forwarding state: 2
Link type is point-to-point by default, Peer is STP
Loop guard is enabled by default on the port
BPDU: sent 6, received 10162
show spanning-tree summary
Switch is in rapid-pvst mode
Root bridge for: none
Extended system ID is enabled
Portfast Default is disabled
PortFast BPDU Guard Default is disabled
Portfast BPDU Filter Default is disabled
Loopguard Default is enabled
EtherChannel misconfig guard is enabled
UplinkFast is disabled
BackboneFast is disabled
Configured Pathcost method used is short
Name Blocking Listening Learning Forwarding STP Active
---------------------- -------- --------- -------- ---------- ----------
VLAN0001 0 0 0 1 1
VLAN0008 0 0 0 2 2
VLAN0010 0 0 0 1 1
show interfaces fa0/1 switchport
Name: Fa0/1
Switchport: Enabled
Administrative Mode: trunk
Operational Mode: trunk
Administrative Trunking Encapsulation: dot1q
Operational Trunking Encapsulation: dot1q
Negotiation of Trunking: On
Access Mode VLAN: 1 (default)
Trunking Native Mode VLAN: 1 (default)
Administrative Native VLAN tagging: enabled
Voice VLAN: none
Administrative private-vlan host-association: none
Administrative private-vlan mapping: none
Administrative private-vlan trunk native VLAN: none
Administrative private-vlan trunk Native VLAN tagging: enabled
Administrative private-vlan trunk encapsulation: dot1q
Administrative private-vlan trunk normal VLANs: none
Administrative private-vlan trunk private VLANs: none
Operational private-vlan: none
Trunking VLANs Enabled: ALL
Pruning VLANs Enabled: 2-1001
Capture Mode Disabled
Capture VLANs Allowed: ALL
Protected: false
Unknown unicast blocked: disabled
Unknown multicast blocked: disabled
Appliance trust: none
!
interface FastEthernet0/1
description --- Link to 4948-cr02 ---
switchport trunk encapsulation dot1q
switchport mode trunk
speed 100
duplex full
end
The interface is connected to MediaConverter than a fiber connects this to the ISP switch. There runs a QinQ service that ends with another fiber and MC to my other switch, the one that is the root bridge 2c54.2d02.b440.
Here is the output from my other end switch:
show spanning-tree interface gi1/30 det
Port 30 (GigabitEthernet1/30) of VLAN0001 is designated forwarding
Port path cost 19, Port priority 128, Port Identifier 128.30.
Designated root has priority 20481, address 2c54.2d02.e300
Designated bridge has priority 20481, address 2c54.2d02.e300
Designated port id is 128.30, designated path cost 0
Timers: message age 0, forward delay 0, hold 0
Number of transitions to forwarding state: 1
Link type is point-to-point by default
BPDU: sent 8965, received 0
Port 30 (GigabitEthernet1/30) of VLAN0008 is designated forwarding
Port path cost 19, Port priority 128, Port Identifier 128.30.
Designated root has priority 24584, address 2c54.2d02.b440
Designated bridge has priority 24584, address 2c54.2d02.e300
Designated port id is 128.30, designated path cost 4
Timers: message age 0, forward delay 0, hold 0
Number of transitions to forwarding state: 1
Link type is point-to-point by default
BPDU: sent 8959, received 0
Port 30 (GigabitEthernet1/30) of VLAN0010 is designated forwarding
Port path cost 19, Port priority 128, Port Identifier 128.30.
Designated root has priority 20490, address 2c54.2d02.e300
Designated bridge has priority 20490, address 2c54.2d02.e300
Designated port id is 128.30, designated path cost 0
Timers: message age 0, forward delay 0, hold 0
Number of transitions to forwarding state: 1
Link type is point-to-point by default
BPDU: sent 8965, received 0
!
interface GigabitEthernet1/30
description --- Uplink to WG building ---
switchport trunk encapsulation dot1q
switchport mode trunk
end
If any importance, CDP seems to work fine on both ends along with VTP (which also works flawlessly).
Of notice that BPDU counters on 2nd switch differ as I reset today "the trouble switch". Any hint would be much appreciated.
Uptime on "the trouble switch" is 4 weeks now, but I scheduled a reboot this night. I also updated today STP mode from IEEE to rapid-pvst, and what it actually did: it sent those 7 BPDUs but nothing more.
