CAM table not updating after STP TCN

I have 2 switches connected back to back on port-channel 1. As per my
understanding after any STP change, I should see CAM table update and shortly
after that ARP table update. I see the ARP being refreshed but it looks like
the CAM table on SW2 didnt update.

SW1# sh ip arp | i 34a8.4eb6.0aa2
172.20.210.38 00:01:10 34a8.4eb6.0aa2 Vlan2010

       
SW1# sh mac add
dy | i 34a8.4eb6.0aa2
* 2010 34a8.4eb6.0aa2 dynamic 0 F
F Eth1/9---> aging time 0 shows that we are getting traffic hitting this
entry continuously. Right?

SW2# sh ip arp | i 34a8.4eb6.0aa2
172.20.210.38
00:01:14 34a8.4eb6.0aa2 Vlan2010

     
SW2# sh mac add dy | i
34a8.4eb6.0aa2
* 2010 34a8.4eb6.0aa2 dynamic 120 F F
Po1----> it seems the CAM timer didn't reset after TCN but the ARP refreshed
The link between the switches are configured like this and these switches are
running HSRP for all the vlans with SW1 being STP root and HSRP primary for
all the vlans

interface port-channel1
  switchport
  switchport mode trunk
 
switchport trunk allowed vlan 2,650,660,720,730,790,1920,1930
  switchport
trunk allowed vlan add 1640,1960,1910,1930,1490,2000,2010
  spanning-tree
link-type point-to-point
  mtu 9216
  load-interval counter 1 60

For arp
there is a command "show ip arp internal event-history" which can show if the
arp was refreshed due to a TCN or not. which command can help in checking if
mac table was refreshed due to TCN or not apart from show mac address table?

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Received on Mon Jan 14 2013 - 02:50:54 ART