Maybe its occurred for your network switches, for your security of switches or Access Layer security, after enabling port security and MAC Address filtering, we want to add another Client or workstation or replace another workstation to the oldest workstation but this not work easily cause Switches Port Security block forwarding frames of new Workstation cause here MAC Address id different so what we can do is that:
for sure this problem is from Switch Port Security, first use :
terminal monitor
to view violations, of course if your portsecurity action is set to restricted and after that you need to sure this workstation is not appended to another ports before connected to this port, and you can be sure by execute this command:
show ports add | inc [yourMACAddress]
then if you have it or registered before on another Ports you need first to remove it via this command:
conf t int [slot/number] #ports already connected to host no swi port mac sti [MAC-Address]
after that time is to view again to sure that MAC Address was cleared via this command:
show ports add | inc [yourMACAddress]
if nothing appears then continue to next command to clear MAC Address from PortSecurity Database:
switch1# clear port sti add [MAC-Address]
and then once shutdown and no shutdown for connected Interface to new Workstation.
then run again this command and in the normal status you dont see any other violation to this new port and workstation:
terminal monitor
