Cisco Nexus 9000 Series Troubleshooting Manual page 70

Troubleshooting STP Data Loops
Command or Action
Designated port id is 128.385, designated path cost 0
Timers: message age 16, forward delay 0, hold 0
Number of transitions to forwarding state: 1
The port type is network by default
Link type is point-to-point by default
BPDU: sent 1265,
Step 6 switch(config-if)# show interface counters errors
Example:
switch(config-if)# show interface counters errors
--------------------------------------------------------------
Port Align-Err FCS-Err Xmit-Err Rcv-Err UnderSize OutDiscards
--------------------------------------------------------------
mgmt0 --
Eth1/1 0
Eth1/2 0
Eth1/3 0
Eth1/4 0
Eth1/5 0
Eth1/6 0
Eth1/7 0
Eth1/8 0
This example shows that the designated port is regularly sending BPDUs:
switch# show spanning-tree interface ethernet 3/1 detail
Port 385 (Ethernet3/1) of VLAN0001 is root forwarding
Port path cost 4, Port priority 128, Port Identifier 128.385
Designated root has priority 32769, address 0018.bad7.db15
Designated bridge has priority 32769, address 0018.bad7.db15
Designated port id is 128.385, designated path cost 0
Timers: message age 16, forward delay 0, hold 0
Number of transitions to forwarding state: 1
The port type is network by default
Link type is point-to-point by default
BPDU: sent 1265, received 1269
This example shows how to check the hardware packet statistic counters for a possible BPDU error drop:
switch# show interface counters errors
--------------------------------------------------------------
Port Align-Err FCS-Err Xmit-Err Rcv-Err UnderSize OutDiscards
--------------------------------------------------------------
mgmt0
Eth1/1
Eth1/2
Eth1/3
Eth1/4
Eth1/5
Eth1/6
Eth1/7
Eth1/8
Cisco Nexus 9000 Series NX-OS Troubleshooting Guide, Release 7.x
58
received 1269
-- -- --
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
-- -- --
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
Purpose
(Optional)
Checks the hardware packet statistic (error
drop) counters.
-- --
0 0
0 0
0 0
0 0
0 0
0 0
0 0
0 0
-- -- --
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
Troubleshooting STP