[c-nsp] Mac address flapping..

Fri Jul 10 13:48:13 EDT 2009

Alan,
 Po1 is the connection from 6509-a to 6509-b.
 G1/7 goes to port G1/1 on 4506-a.
 G1/8 goes to G1/1 on 4506-b.

As for them creating a loop locally, If I disable one of the ports facing them, the errors persist.  Them having a loop in their switch, if it only has a single connection to my network, shouldn't effect me.  Unless I am missing something..

Could their configuration actually effect my spanning tree if I am only running one link to them??

James

-----Original Message-----
From: cisco-nsp-bounces at puck.nether.net [mailto:cisco-nsp-bounces at puck.nether.net] On Behalf Of James Ashton
Sent: Friday, July 10, 2009 11:57 AM
To: cisco-nsp at puck.nether.net
Subject: [c-nsp] Mac address flapping..

Hello all.

I am seeing a log of Mac_Move log entries for one vlan on my 6509s. (I have a pair doing redundant gateways for a DataCenter network)

       %MAC_MOVE-SP-4-NOTIF: Host 00d0.009e.2400 in vlan 42 is flapping between port Po1 and port Gi1/7

I see about 20 of these for this one vlan each minute.
Spanning tree is not reconverging.  It hasn't had a topology change in over 48 hours.
HSRP has not changed state.
I have over 120 vlans set up in this exact manor and this is the only one going this.

I have default timers set on HSRP and Spanning tree.
Gateways are all on SVIs.
Trunks between the 6509s and then a full mesh out to a pair of 4506s doing customer distro.

The above log entries are the only ones I am seeing from all 4 devices.   And they are only coming from    6509-a

I am running out of ideas as to the cause.   If I disconnect the customer from 4506-b or -a  so they only have one link and are no longer part of spanning tree.  It doesn't stop.  So I assume that their switch is not the cause.

Any thoughts??

=================================================
The vlan interface config is:
interface Vlan42
 description Customer1
 ip address xxx.xxx.xxx.xxx 255.255.255.224 secondary
 ip address xxx.xxx.xxx.xxx 255.255.255.224
 no ip redirects
 no ip unreachables
 no ip proxy-arp
 standby 42 ip xxx.xxx.xxx.xxx
 standby 42 ip xxx.xxx.xxx.xxx secondary
 standby 42 priority 110
 standby 42 preempt

On the second 6509 the config is:
interface Vlan42
 description Customer1
 ip address xxx.xxx.xxx.xxx 255.255.255.224 secondary
 ip address xxx.xxx.xxx.xxx 255.255.255.224
 no ip redirects
 no ip unreachables
 no ip proxy-arp
 standby 42 ip xxx.xxx.xxx.xxx
 standby 42 ip xxx.xxx.xxx.xxx secondary
  standby 42 preempt

6509-a:
VLAN0042
  Spanning tree enabled protocol ieee
  Root ID    Priority    24618
             Address     00d0.00a7.f000
             This bridge is the root
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec

  Bridge ID  Priority    24618  (priority 24576 sys-id-ext 42)
             Address     00d0.00a7.f000
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
             Aging Time 300

Interface        Role Sts Cost      Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Gi1/7            Desg FWD 4         128.7    P2p 
Gi1/8            Desg FWD 4         128.8    P2p 
Po1              Desg FWD 3         128.1665 P2p

6509-b:
VLAN0042
  Spanning tree enabled protocol ieee
  Root ID    Priority    24618
             Address     00d0.00a7.f000
             Cost        3
             Port        1665 (Port-channel1)
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec

  Bridge ID  Priority    28714  (priority 28672 sys-id-ext 42)
             Address     00d0.009e.2400
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
             Aging Time 300

Interface        Role Sts Cost      Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Gi1/7            Desg FWD 4         128.7    P2p 
Gi1/8            Desg FWD 4         128.8    P2p 
Po1              Root FWD 3         128.1665 P2p

4506-a:
VLAN0042
  Spanning tree enabled protocol ieee
  Root ID    Priority    24618
             Address     00d0.00a7.f000
             Cost        3004
             Port        1 (GigabitEthernet1/1)
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec

  Bridge ID  Priority    49194  (priority 49152 sys-id-ext 42)
             Address     0013.c405.7dc0
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
             Aging Time 300
  Uplinkfast enabled

Interface        Role Sts Cost      Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Gi1/1            Root FWD 3004      128.1    P2p 
Gi1/2            Altn BLK 3004      128.2    P2p 
Fa3/25           Desg FWD 3019      128.153  P2p

4506-b:
VLAN0042
  Spanning tree enabled protocol ieee
  Root ID    Priority    24618
             Address     00d0.00a7.f000
             Cost        3004
             Port        2 (GigabitEthernet1/2)
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec

  Bridge ID  Priority    49194  (priority 49152 sys-id-ext 42)
             Address     0014.6aed.3b80
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
             Aging Time 300
  Uplinkfast enabled

Interface        Role Sts Cost      Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Gi1/1            Altn BLK 3004      128.1    P2p 
Gi1/2            Root FWD 3004      128.2    P2p 
Fa3/25           Desg FWD 3019      128.153  P2p

James P. Ashton
Sr. Network Engineer
E Solutions Corporation
813.301.2642 Direct
813.301.2600 Main
813.301.2699 Fax
813.301.2620 Support

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