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Nexus 4001i and MST tons of log errors

Went looking through my Nexus 4001i logs today, and started noticing a bunch of STP role and port change messages:

2013 Jul  5 14:40:31 N4k-SLOT7-SW1 %STP-6-PORT_ROLE: Port Ethernet1/1 instance MST0000 role changed to designated

2013 Jul  5 14:40:31 N4k-SLOT7-SW1 %STP-6-PORT_ROLE: Port port-channel2 instance MST0000 role changed to alternate

2013 Jul  5 14:40:32 N4k-SLOT7-SW1 %STP-6-PORT_ROLE: Port port-channel1 instance MST0000 role changed to root

2013 Jul  5 14:40:32 N4k-SLOT7-SW1 %STP-6-MST_PORT_BOUNDARY: Port Ethernet1/14 removed as MST Boundary port

2013 Jul  5 14:40:32 N4k-SLOT7-SW1 %STP-6-PORT_ROLE: Port Ethernet1/14 instance MST0000 role changed to designated

2013 Jul  5 14:40:32 N4k-SLOT7-SW1 %STP-6-MST_PORT_BOUNDARY: Port Ethernet1/13 removed as MST Boundary port

2013 Jul  5 14:40:32 N4k-SLOT7-SW1 %STP-6-PORT_ROLE: Port Ethernet1/13 instance MST0000 role changed to designated

2013 Jul  5 14:40:32 N4k-SLOT7-SW1 %STP-6-MST_PORT_BOUNDARY: Port Ethernet1/12 removed as MST Boundary port

2013 Jul  5 14:40:32 N4k-SLOT7-SW1 %STP-6-PORT_ROLE: Port Ethernet1/12 instance MST0000 role changed to designated

2013 Jul  5 14:40:32 N4k-SLOT7-SW1 %STP-6-MST_PORT_BOUNDARY: Port Ethernet1/11 removed as MST Boundary port

2013 Jul  5 14:40:32 N4k-SLOT7-SW1 %STP-6-PORT_ROLE: Port Ethernet1/11 instance MST0000 role changed to designated

2013 Jul  5 14:40:32 N4k-SLOT7-SW1 %STP-6-MST_PORT_BOUNDARY: Port Ethernet1/10 removed as MST Boundary port

2013 Jul  5 14:40:32 N4k-SLOT7-SW1 %STP-6-PORT_ROLE: Port Ethernet1/10 instance MST0000 role changed to designated

2013 Jul  5 14:40:32 N4k-SLOT7-SW1 %STP-6-MST_PORT_BOUNDARY: Port Ethernet1/9 removed as MST Boundary port

2013 Jul  5 14:40:32 N4k-SLOT7-SW1 %STP-6-PORT_ROLE: Port Ethernet1/9 instance MST0000 role changed to designated

2013 Jul  5 14:40:32 N4k-SLOT7-SW1 %STP-6-MST_PORT_BOUNDARY: Port Ethernet1/8 removed as MST Boundary port

2013 Jul  5 14:40:32 N4k-SLOT7-SW1 %STP-6-PORT_ROLE: Port Ethernet1/8 instance MST0000 role changed to designated

2013 Jul  5 14:40:32 N4k-SLOT7-SW1 %STP-6-MST_PORT_BOUNDARY: Port Ethernet1/7 removed as MST Boundary port

2013 Jul  5 14:40:32 N4k-SLOT7-SW1 %STP-6-PORT_ROLE: Port Ethernet1/7 instance MST0000 role changed to designated

2013 Jul  5 14:40:32 N4k-SLOT7-SW1 %STP-6-MST_PORT_BOUNDARY: Port Ethernet1/6 removed as MST Boundary port

2013 Jul  5 14:40:32 N4k-SLOT7-SW1 %STP-6-PORT_ROLE: Port Ethernet1/6 instance MST0000 role changed to designated

2013 Jul  5 14:40:32 N4k-SLOT7-SW1 %STP-6-MST_PORT_BOUNDARY: Port Ethernet1/5 removed as MST Boundary port

2013 Jul  5 14:40:32 N4k-SLOT7-SW1 %STP-6-PORT_ROLE: Port Ethernet1/5 instance MST0000 role changed to designated

2013 Jul  5 14:40:32 N4k-SLOT7-SW1 %STP-6-MST_PORT_BOUNDARY: Port Ethernet1/4 removed as MST Boundary port

2013 Jul  5 14:40:32 N4k-SLOT7-SW1 %STP-6-PORT_ROLE: Port Ethernet1/4 instance MST0000 role changed to designated

2013 Jul  5 14:40:32 N4k-SLOT7-SW1 %STP-6-MST_PORT_BOUNDARY: Port Ethernet1/3 removed as MST Boundary port

2013 Jul  5 14:40:32 N4k-SLOT7-SW1 %STP-6-PORT_ROLE: Port Ethernet1/3 instance MST0000 role changed to designated

2013 Jul  5 14:40:32 N4k-SLOT7-SW1 %STP-6-MST_PORT_BOUNDARY: Port Ethernet1/2 removed as MST Boundary port

2013 Jul  5 14:40:32 N4k-SLOT7-SW1 %STP-6-PORT_ROLE: Port Ethernet1/2 instance MST0000 role changed to designated

2013 Jul  5 14:40:32 N4k-SLOT7-SW1 %STP-6-MST_PORT_BOUNDARY: Port Ethernet1/1 removed as MST Boundary port

After going through a variety of configuration validations, spanning-tree root and priority validations as well as making sure the instances and revisions between the various MST speaking switches (all of the Nexus gear including Nexus 5596 which are vPC peers, 4001i's which connect via vPC's to the 5596's, and Catalyst 3110X's which also use MST, but only have one uplink at this time to the 5596's not in a vPC setup).

None of the other devices appear to be experiencing this problem.

I am quite confused as to what is going on, and cannot figure out why the 4001i is wigging out like this.

A quick output of MST::

N4k-SLOT7-SW1# show spanning-tree mst

##### MST0    vlans mapped:   801-3109,3111-4094

Bridge        address 6073.5c8d.7e82  priority      24576 (24576 sysid 0)

Root          address 0023.04ee.be03  priority      16384 (16384 sysid 0)

              port    Po1             path cost     0       

Regional Root address 0023.04ee.be03  priority      16384 (16384 sysid 0)

                                      internal cost 500       rem hops 19

Operational   hello time 2 , forward delay 15, max age 20, txholdcount 6

Configured    hello time 2 , forward delay 15, max age 20, max hops    20

Interface        Role Sts Cost      Prio.Nbr Type

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

Po1              Root FWD 500        32.4096 P2p

Po2              Altn BLK 1000       64.4097 P2p

Eth1/1           Desg FWD 2000      128.129  Edge P2p

Eth1/2           Desg FWD 2000      128.130  Edge P2p

Eth1/3           Desg FWD 2000      128.131  Edge P2p

Eth1/4           Desg FWD 2000      128.132  Edge P2p

Eth1/5           Desg FWD 2000      128.133  Edge P2p

Eth1/6           Desg FWD 2000      128.134  Edge P2p

Eth1/7           Desg FWD 2000      128.135  Edge P2p

Eth1/8           Desg FWD 2000      128.136  Edge P2p

Eth1/9           Desg FWD 2000      128.137  Edge P2p

Eth1/10          Desg FWD 2000      128.138  Edge P2p

Eth1/11          Desg FWD 2000      128.139  Edge P2p

Eth1/12          Desg FWD 2000      128.140  Edge P2p

Eth1/13          Desg FWD 2000      128.141  Edge P2p

Eth1/14          Desg FWD 2000      128.142  Edge P2p

##### MST1    vlans mapped:   2-499,600-800,3110

Bridge        address 6073.5c8d.7e82  priority      24577 (24576 sysid 1)

Root          address 0023.04ee.be03  priority      16385 (16384 sysid 1)

              port    Po1             cost          500       rem hops 19

Interface        Role Sts Cost      Prio.Nbr Type

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

Po1              Root FWD 500       128.4096 P2p

Eth1/1           Desg FWD 2000      128.129  Edge P2p

Eth1/2           Desg FWD 2000      128.130  Edge P2p

Eth1/3           Desg FWD 2000      128.131  Edge P2p

Eth1/4           Desg FWD 2000      128.132  Edge P2p

Eth1/5           Desg FWD 2000      128.133  Edge P2p

Eth1/6           Desg FWD 2000      128.134  Edge P2p

Eth1/7           Desg FWD 2000      128.135  Edge P2p

Eth1/8           Desg FWD 2000      128.136  Edge P2p

Eth1/9           Desg FWD 2000      128.137  Edge P2p

Eth1/10          Desg FWD 2000      128.138  Edge P2p

Eth1/11          Desg FWD 2000      128.139  Edge P2p

Eth1/12          Desg FWD 2000      128.140  Edge P2p

Eth1/13          Desg FWD 2000      128.141  Edge P2p

Eth1/14          Desg FWD 2000      128.142  Edge P2p

##### MST2    vlans mapped:   1,500-599

Bridge        address 6073.5c8d.7e82  priority      24578 (24576 sysid 2)

Root          address 0023.04ee.be03  priority      16386 (16384 sysid 2)

              port    Po2             cost          1000      rem hops 19

Interface        Role Sts Cost      Prio.Nbr Type

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

Po2              Root FWD 1000      128.4097 P2p

Eth1/1           Desg FWD 2000      128.129  Edge P2p

Eth1/2           Desg FWD 2000      128.130  Edge P2p

Eth1/3           Desg FWD 2000      128.131  Edge P2p

Eth1/4           Desg FWD 2000      128.132  Edge P2p

Eth1/5           Desg FWD 2000      128.133  Edge P2p

Eth1/6           Desg FWD 2000      128.134  Edge P2p

Eth1/7           Desg FWD 2000      128.135  Edge P2p

Eth1/8           Desg FWD 2000      128.136  Edge P2p

Eth1/9           Desg FWD 2000      128.137  Edge P2p

Eth1/10          Desg FWD 2000      128.138  Edge P2p

Eth1/11          Desg FWD 2000      128.139  Edge P2p

Eth1/12          Desg FWD 2000      128.140  Edge P2p

Eth1/13          Desg FWD 2000      128.141  Edge P2p

Eth1/14          Desg FWD 2000      128.142  Edge P2p

N4k-SLOT7-SW1# show spanning-tree detail | i occur|from|exec

MST0000 is executing the mstp compatible Spanning Tree protocol

  Number of topology changes 1 last change occurred 3:48:09 ago

          from port-channel1

MST0001 is executing the mstp compatible Spanning Tree protocol

  Number of topology changes 1 last change occurred 3:48:07 ago

          from port-channel1

MST0002 is executing the mstp compatible Spanning Tree protocol

  Number of topology changes 1 last change occurred 3:48:07 ago

          from port-channel2

(topology change was due to testing rapid-PVST for this switch, and then putting it back, the previous change occured 555 hours ago).

N4k-SLOT9-SW2# show spanning-tree

MST0000

  Spanning tree enabled protocol mstp

  Root ID    Priority    16384

             Address     0023.04ee.be03

             Cost        0

             Port        4096 (port-channel1)

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

  Bridge ID  Priority    24576  (priority 24576 sys-id-ext 0)

             Address     2c54.2ded.b704

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

Interface        Role Sts Cost      Prio.Nbr Type

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

Po1              Root FWD 500       128.4096 P2p

Po2              Altn BLK 1000      128.4097 P2p

Eth1/1           Desg FWD 2000      128.129  Edge P2p

Eth1/2           Desg FWD 2000      128.130  Edge P2p

Eth1/3           Desg FWD 2000      128.131  Edge P2p

Eth1/4           Desg FWD 2000      128.132  Edge P2p

Eth1/5           Desg FWD 2000      128.133  Edge P2p

Eth1/6           Desg FWD 2000      128.134  Edge P2p

Eth1/7           Desg FWD 2000      128.135  Edge P2p

Eth1/8           Desg FWD 2000      128.136  Edge P2p

Eth1/9           Desg FWD 2000      128.137  Edge P2p

Eth1/10          Desg FWD 2000      128.138  Edge P2p

Eth1/11          Desg FWD 2000      128.139  Edge P2p

Eth1/12          Desg FWD 2000      128.140  Edge P2p

Eth1/13          Desg FWD 2000      128.141  Edge P2p

Eth1/14          Desg FWD 2000      128.142  Edge P2p

MST0001

  Spanning tree enabled protocol mstp

  Root ID    Priority    16385

             Address     0023.04ee.be03

             Cost        500

             Port        4096 (port-channel1)

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

  Bridge ID  Priority    24577  (priority 24576 sys-id-ext 1)

             Address     2c54.2ded.b704

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

Interface        Role Sts Cost      Prio.Nbr Type

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

Po1              Root FWD 500       128.4096 P2p

Eth1/1           Desg FWD 2000      128.129  Edge P2p

Eth1/2           Desg FWD 2000      128.130  Edge P2p

Eth1/3           Desg FWD 2000      128.131  Edge P2p

Eth1/4           Desg FWD 2000      128.132  Edge P2p

Eth1/5           Desg FWD 2000      128.133  Edge P2p

Eth1/6           Desg FWD 2000      128.134  Edge P2p

Eth1/7           Desg FWD 2000      128.135  Edge P2p

Eth1/8           Desg FWD 2000      128.136  Edge P2p

Eth1/9           Desg FWD 2000      128.137  Edge P2p

Eth1/10          Desg FWD 2000      128.138  Edge P2p

Eth1/11          Desg FWD 2000      128.139  Edge P2p

Eth1/12          Desg FWD 2000      128.140  Edge P2p

Eth1/13          Desg FWD 2000      128.141  Edge P2p

Eth1/14          Desg FWD 2000      128.142  Edge P2p

MST0002

  Spanning tree enabled protocol mstp

  Root ID    Priority    16386

             Address     0023.04ee.be03

             Cost        1000

             Port        4097 (port-channel2)

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

  Bridge ID  Priority    24578  (priority 24576 sys-id-ext 2)

             Address     2c54.2ded.b704

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

Interface        Role Sts Cost      Prio.Nbr Type

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

Po2              Root FWD 1000      128.4097 P2p

Eth1/1           Desg FWD 2000      128.129  Edge P2p

Eth1/2           Desg FWD 2000      128.130  Edge P2p

Eth1/3           Desg FWD 2000      128.131  Edge P2p

Eth1/4           Desg FWD 2000      128.132  Edge P2p

Eth1/5           Desg FWD 2000      128.133  Edge P2p

Eth1/6           Desg FWD 2000      128.134  Edge P2p

Eth1/7           Desg FWD 2000      128.135  Edge P2p

Eth1/8           Desg FWD 2000      128.136  Edge P2p

Eth1/9           Desg FWD 2000      128.137  Edge P2p

Eth1/10          Desg FWD 2000      128.138  Edge P2p

Eth1/11          Desg FWD 2000      128.139  Edge P2p

Eth1/12          Desg FWD 2000      128.140  Edge P2p

Eth1/13          Desg FWD 2000      128.141  Edge P2p

Eth1/14          Desg FWD 2000      128.142  Edge P2p

N4k-SLOT9-SW2#  show spanning-tree detail | i occur|from|exec

MST0000 is executing the mstp compatible Spanning Tree protocol

  Number of topology changes 18758 last change occurred 4:01:03 ago

          from port-channel1

MST0001 is executing the mstp compatible Spanning Tree protocol

  Number of topology changes 45742 last change occurred 4:01:02 ago

          from port-channel1

MST0002 is executing the mstp compatible Spanning Tree protocol

  Number of topology changes 21007 last change occurred 599:47:47 ago

          from port-channel2

N4k-SLOT9-SW2#

N5596-DC-SW1# show spanning-tree

MST0000

  Spanning tree enabled protocol mstp

  Root ID    Priority    16384

             Address     0023.04ee.be03

             This bridge is the root

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

  Bridge ID  Priority    16384  (priority 16384 sys-id-ext 0)

             Address     0023.04ee.be03

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

Interface        Role Sts Cost      Prio.Nbr Type

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

Po1              Desg FWD 1000      128.4096 P2p

Po2              Desg FWD 200       128.4097 (vPC) P2p

Po3              Desg FWD 200       128.4098 (vPC) P2p

Po57             Desg FWD 200       128.4152 (vPC) P2p

Po100            Desg FWD 1000      128.4195 (vPC peer-link) Network P2p

Eth1/15          Desg FWD 2000      128.143  Edge P2p

Eth1/16          Desg FWD 2000      128.144  Edge P2p

MST0001

  Spanning tree enabled protocol mstp

  Root ID    Priority    16385

             Address     0023.04ee.be03

             This bridge is the root

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

  Bridge ID  Priority    16385  (priority 16384 sys-id-ext 1)

             Address     0023.04ee.be03

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

Interface        Role Sts Cost      Prio.Nbr Type

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

Po2              Desg FWD 200       128.4097 (vPC) P2p

Po3              Desg FWD 200       128.4098 (vPC) P2p

Po57             Desg FWD 200       128.4152 (vPC) P2p

Po100            Desg FWD 1000      128.4195 (vPC peer-link) Network P2p

MST0002

  Spanning tree enabled protocol mstp

  Root ID    Priority    16386

             Address     0023.04ee.be03

             This bridge is the root

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

  Bridge ID  Priority    16386  (priority 16384 sys-id-ext 2)

             Address     0023.04ee.be03

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

Interface        Role Sts Cost      Prio.Nbr Type

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

Po1              Desg FWD 1000      128.4096 P2p

Eth1/15          Desg FWD 2000      128.143  Edge P2p

Eth1/16          Desg FWD 2000      128.144  Edge P2p

N5596-DC-SW1# show spanning-tree detail | i occur|from|exec

MST0000 is executing the mstp compatible Spanning Tree protocol

  Number of topology changes 44578 last change occurred 4:11:57 ago

          from port-channel2

MST0001 is executing the mstp compatible Spanning Tree protocol

  Number of topology changes 98707 last change occurred 4:11:55 ago

          from port-channel2

MST0002 is executing the mstp compatible Spanning Tree protocol

  Number of topology changes 4 last change occurred 4:11:55 ago

          from port-channel1

N5596-DC-SW2# show spanning-tree

MST0000

  Spanning tree enabled protocol mstp

  Root ID    Priority    16384

             Address     0023.04ee.be03

             This bridge is the root

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

  Bridge ID  Priority    16384  (priority 16384 sys-id-ext 0)

             Address     0023.04ee.be03

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

Interface        Role Sts Cost      Prio.Nbr Type

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

Po1              Desg FWD 1000      128.4096 P2p

Po2              Desg FWD 200       128.4097 (vPC) P2p

Po3              Desg FWD 200       128.4098 (vPC) P2p

Po57             Desg FWD 200       128.4152 (vPC) P2p

Po100            Root FWD 1000      128.4195 (vPC peer-link) Network P2p

Eth1/9           Desg FWD 20000     128.137  P2p

Eth1/15          Desg FWD 2000      128.143  Edge P2p

Eth1/16          Desg FWD 2000      128.144  Edge P2p

MST0001

  Spanning tree enabled protocol mstp

  Root ID    Priority    16385

             Address     0023.04ee.be03

             This bridge is the root

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

  Bridge ID  Priority    16385  (priority 16384 sys-id-ext 1)

             Address     0023.04ee.be03

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

Interface        Role Sts Cost      Prio.Nbr Type

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

Po2              Desg FWD 200       128.4097 (vPC) P2p

Po3              Desg FWD 200       128.4098 (vPC) P2p

Po57             Desg FWD 200       128.4152 (vPC) P2p

Po100            Root FWD 1000      128.4195 (vPC peer-link) Network P2p

Eth1/9           Desg FWD 20000     128.137  P2p

MST0002

  Spanning tree enabled protocol mstp

  Root ID    Priority    16386

             Address     0023.04ee.be03

             This bridge is the root

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

  Bridge ID  Priority    16386  (priority 16384 sys-id-ext 2)

             Address     0023.04ee.be03

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

Interface        Role Sts Cost      Prio.Nbr Type

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

Po1              Desg FWD 1000      128.4096 P2p

Eth1/9           Desg FWD 20000     128.137  P2p

Eth1/15          Desg FWD 2000      128.143  Edge P2p

Eth1/16          Desg FWD 2000      128.144  Edge P2p

N5596-DC-SW2# show spanning-tree | i occur|from|exec

N5596-DC-SW2# show spanning-tree detail | i occur|from|exec

MST0000 is executing the mstp compatible Spanning Tree protocol

  Number of topology changes 44234 last change occurred 4:12:45 ago

          from port-channel100

MST0001 is executing the mstp compatible Spanning Tree protocol

  Number of topology changes 97804 last change occurred 4:12:43 ago

          from port-channel100

MST0002 is executing the mstp compatible Spanning Tree protocol

  Number of topology changes 49801 last change occurred 599:58:06 ago

          from Ethernet1/9

Except from MST configs:

Nexus 4001i switches:

vlan 1,301-499

vlan 500

  fip-snooping enable

vlan 600-800

spanning-tree mode mst

spanning-tree pathcost method long

spanning-tree mst 0-2 priority 24576

spanning-tree mst configuration

  revision 1

  instance 1 vlan 2-499,600-800,3110

  instance 2 vlan 1,500-599

Nexus 5596 switches:

N5596-DC-SW1

spanning-tree mode mst

spanning-tree pathcost method long

spanning-tree mst 0-2 priority 16384

spanning-tree pseudo-information

  mst 0-2 root priority 16384

  mst 0-2 designated priority 16384

spanning-tree mst configuration

  revision 1

  instance 1 vlan 2-499,600-800,3110

  instance 2 vlan 1,500-599

N5596-DC-SW2

spanning-tree mode mst

spanning-tree pathcost method long

spanning-tree mst 0-2 priority 16384

spanning-tree vlan 3110 priority 24576

spanning-tree pseudo-information

  mst 0-1 designated priority 20480

  mst 2 designated priority 16384

  vlan 1-499,501,600-800 designated priority 20480

spanning-tree mst configuration

  revision 1

  instance 1 vlan 2-499,600-800,3110

  instance 2 vlan 1,500-599

5596's vPC configs

N5596-DC-SW1

vpc domain 3

  peer-switch

  role priority 100

  peer-keepalive destination 192.168.92.223 source 192.168.92.222

  auto-recovery

N5596-DC-SW2

vpc domain 3

  peer-switch

  role priority 200

  peer-keepalive destination 192.168.92.222 source 192.168.92.223

  auto-recovery

Quick rundown of connections between devices:

Nexus 4001's connect to Nexus 5596's for ethernet data via twinax cables in a four port vPC between both Nexus 5596's.

Nexus 4001's connect to one Nexus 5596 a piece for FCoE two port LACP port channel. (hence the two instances, and vlan 1,500-599 in the same instance)

Catalyst 3110X connects via one Fiber-Optic connection to the N5596-DC-SW2, eventually will have two in a port-channel

Also keep in mind I corrected a priority conflict between the 3110X and Nexus 5596's earlier last month, which would explain all of the topology changes.

I can provide any other information if it is useful. I am just confused!

Everyone's tags (4)
4 REPLIES
Community Member

Nexus 4001i and MST tons of log errors

To add to this, the logs I am seeing are constantly repeating. This isn't just a single instance of the problem, and when running debugs of spanning-tree and bpdu_rx, the only ports on the 4001i's receiving BPDU's are the port-channel uplinks. The ports themselves do not seem to transition out of a designated state, they just keep saying they are being reflagged as designated.

Community Member

Re: Nexus 4001i and MST tons of log errors

I identified the problem.

Refer to

http://www.cisco.com/en/US/docs/switches/datacenter/sw/4_2/nx-os/interfaces/configuration/guide/if_vPC.html

for more information.

The problem I encountered was self-inflicted.

Using the spanning-tree pseudo-information command creates a psuedo priority setup that if implemented after the global spanning-tree commands sits alongside the spanning-tree priority and vlan definitions. This is intended to allow for non-vPC VLANs to have their own spanning-tree definitions separate of the spanning-tree environment for the vPC vlans. I am not sure the best way to describe it, but if you are not running a hybrid vPC setup (where you have vPC member VLANs and non-vPC VLANS with a separate link between the 5596's for the non-vPC VLANs) this setup would help you ensure you have a stable spanning-tree and prevent unnecessary blocking.

When I enabled this command, I applied it to the vPC VLAN's as well, and that caused the Nexus 4001i's vPC links to constantly change port role, and update all of the edge ports subsequently. While I didn't see a performance impact to end hosts (not much traffic is on the Nexus DataCenter environment yet), I did get a torrent of logs as shown above.

Once I removed the spanning-tree pseudo-information, the switches quieted down and spanning-tree stabilized on the Nexus 4001i's.

I will revisit the configuration though for trunks not using vPC if it is needed.

Re:Nexus 4001i and MST tons of log errors

Thank you for sharing the resolution too.


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Re:Nexus 4001i and MST tons of log errors

We all get better when we all have the answers. I hope someone learns from my mistakes and does not have to frustrate themselves over the same issues!

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