Span port on switch?

whiteford · ‎11-04-2007

Hi,

I need to monitor traffic on a port on a Cisco 2950 Catalyst switch, I think I need to use the Span option, if so how? Also does it impact cpu/memory on the switch if I have more than one?

Richard Burts · ‎11-04-2007

Andy

The SPAN function (called the monitor function in some switches) will copy traffic to or from a port (or several ports) on the switch and send the copy to another port on the switch. You would need to connect something to that port to do the monitoring. Frequently people connect a PC to the port and run a packet capture software on the PC such as Wireshark (used to be Ethereal) or Sniffer, or some such software.

Catalyst switches can support 2 SPAN/monitor ports. As far as I know there is minimal impact in the switch to run SPAN.

HTH

Rick

HTH

Rick

whiteford · ‎11-04-2007

Thanks, so could I span a vlan to a port?

royalblues · ‎11-04-2007

yes you can configue vlans / port or ports as your span source

this link will let you know the characteristics of source vlan in a span session

http://www.cisco.com/warp/public/473/41.html#charac_source_vlan

HTH

Narayan