Several common Cisco switch port listening configurations

Catalyst 2900xl/3500xl/2950 Series switch Port listening configuration

The following command configures Port sniffing:

Port Monitor

For example, F0/1 and F0/2, F0/2 are VLAN1,F0/1 listening F0/2, F0/2 ports:

Interface FASTETHERNET0/1

Port Monitor FASTETHERNET0/2

Port Monitor FASTETHERNET0/5

Port Monitor VLAN1

2. Catalyst 4000,5000,and 6000 Series switch Port listening configuration

The following command configures Port sniffing:

Set span

For example, Port 1 and Port 2 in Module 6 are VLAN1, Port 3 is in VLAN2, ports 4 and 5 are in VLAN2, Port 2 listens on ports 1 and 3, 4, 5,

Set span 6/1,6/3-5 6/2

The following command prohibits port sniffing:

Set span disable [Dest_mod/dest_port|all]