How to create a mac access-list and an vlan access-map
Last few days at work, we noticed on several access-switches a mac address flapping.
I don’t know how to troubleshoot and to fix it for interim arrangement purposes.
The syslog error message looks like this.
On SW1 at port fa0/20 and fa0/21, there were a telephone switchboard that operate at vlan 102.
On the access-switch with the troubleport, there were a client that causes the problem.
My decision was to filter the mac address at Port gi2/2 on SW2. (only for arrangement purposes)
There are 3 ways to filter mac addresses in my case
- Block the mac address on a dedicated Port
- Block the mac address for a specific vlan for the whole switch with a vlan access-map
- Block the mac address for the whole switch with a static mac address drop statement