I have 4500 switch at distribution level and one access switch 3750 is connected to it.
On my entire network vlan 1 is shut on every switches and Native vlan is 99.
During connection of second uplink to 4500 switch, I forgot to add native vlan command on access switch, so as by default it took vlan 1 as a native vlan.
Because of that I was not able to logging in to access switch and I observer that there was high CPU utilization of all the switches and topology change traps were observed for all the vlan.
As soon as I add native vlan 99 command in trunk, CPU utilization of all the switches came to normal.
I don't understand why native vlan mismatch affect the CPU utilization of my network switches. Please let me explain