Port Security defaults for dynamic learning?

severance26

Hi all,

Reviewing some CCENT stuff-
2.7 Configure, verify, and troubleshoot port security
2.7.a Static
2.7.b Dynamic
2.7.c Sticky
2.7.d Max MAC addresses

Is dynamic the default? Even if I configure a static address, there is no turning dynamic off? In which case, new incoming (dynamic) addresses on a port with security enabled (and given max hasnt been reached) will add them to the MAC table in sh mac add secure?

If this is correct, the only way to make the port static will be to define X static MACs and switchport port-security maximum X.

Your help is always appreciated.

rob42

Yes, dynamic is the default, and, no you can't turn dynamic off. So, if a different device is connected to that port, the switch will dynamically relearn the new MAC address.

To secure the port, without having the type every MAC address (who has the time for that!), you use the 'sticky' option. This provides static addresses, dynamically, placing the MAC addresses into the running-config.