SITE A

Switch_SITE_A(config-if)#do sho cdp nei
Capability Codes: R - Router, T - Trans Bridge, B - Source Route Bridge
                  S - Switch, H - Host, I - IGMP, r - Repeater, P - Phone

Device ID        Local Intrfce     Holdtme    Capability  Platform  Port ID
NGN2BACKUP_SiteA Gig 2/6           163           S I      WS-C3750E Gig 1/0/1 
Switch_SITE_A    Gig 1/6           122          R S I     WS-C4510R Gig 1/6

Switch_SITE_A(config-if)#do sho spann su
Switch is in 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 disabled
EtherChannel misconfig guard is enabled
UplinkFast                   is enabled
BackboneFast                 is enabled
Configured Pathcost method used is short

Name                   Blocking Listening Learning Forwarding STP Active
---------------------- -------- --------- -------- ---------- ----------
VLAN0001                     1         0        0         12         13


Switch_SITE_A(config-if)#do sho spann

VLAN0001
  Spanning tree enabled protocol ieee
  Root ID    Priority    49153
             Address     001e.7a88.8c00
             Cost        3002
             Port        321 (TenGigabitEthernet6/1)
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec

  Bridge ID  Priority    49153  (priority 49152 sys-id-ext 1)
             Address     001f.9e9e.c6c0
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
             Aging Time 300
  Uplinkfast enabled

Interface           Role Sts Cost      Prio.Nbr Type
------------------- ---- --- --------- -------- --------------------------------
Gi1/6               Desg FWD 3004       16.6    P2p
Gi2/6               Desg FWD 20000000  128.70   P2p


Switch_SITE_Asho log
050186: Aug 28 17:48:25.738 EDT: %C4K_EBM-4-HOSTFLAPPING: Host 00:1F:CA:3E:76:3F in vlan 101 is flapping between port Gi2/6 and port Gi1/6
050187: Aug 28 17:48:25.950 EDT: %C4K_EBM-4-HOSTFLAPPING: Host 00:1F:CA:3E:76:3F in vlan 133 is flapping between port Gi1/6 and port Gi2/6
050188: Aug 28 17:48:25.998 EDT: %C4K_EBM-4-HOSTFLAPPING: Host 00:1F:CA:3E:76:3F in vlan 300 is flapping between port Gi2/6 and port Gi1/6
050189: Aug 28 17:48:25.998 EDT: %C4K_EBM-4-HOSTFLAPPING: Host 00:1F:CA:3E:76:3F in vlan 116 is flapping between port Gi2/6 and port Gi1/6