Hi ,

i have one issue with 2924 series switch. i have configured the port security with the following commands:

config t

int fas0/1

po sec

po sec max 1

po sec vio shut

assume that i have connected pc "A" to fas 0/1 interface and the port binds the mac of  pc "A".

But after few days the port got violated with the unknown mac and i noticed that the unknown mac almost matches with the pc "A" mac (except 3 to 4 bits) of mac that was learned by that port. Why it happens? from where did this unknown mac come from? why it is alomost similar to the pc A mac?

plz help me.

regards,

rammi.