Difference between last known last-src-addr and secure-scr-address?

farcry800 · ‎07-13-2007

Hi,

I am new to port security and was wondering what the difference was between the last known last-src-addr and secure-scr-address?

Thanks all.

Jon Marshall · ‎07-13-2007

Hi

As i understand it the secure-src-address is the list of allowed mac-addresses that cn be seen by the switch on that port.

The last-src-address is the last mac-address that has actually been seen by the switch on that port.

HTH

Jon

farcry800 · ‎07-13-2007

Thanks Jon. How do these differ if there is a hub plugged into the jack and teh max addr is 3 for example?

What is the last mac addr. then?

Jon Marshall · ‎07-13-2007

If it is a hub the last-mac-addr will still be the last mac-address seen on that switch port. If you have set the max to 3 and the hub has more than 3 clients then it will probably end up seeing more than 3 mac-addresses and then the violation will kick in.

Indeed stopping people connecting hubs into floor ports is on of the main reasons we use port-security where i work. We restrict the max addresses to 1 which works fine for clients.

Edit - works fine that is until some of our more adventurous users decide to start swapping over their pc's in the floor ports. They usually only do it once :)

HTH

Jon