SPAN sniffer

[leepeiwai]

Hi,

I have configured SPAN for Cisco 3750 to monitor the VLAN traffic for a trunk port.

What tools or command I can use to find out the total traffic for that vlan port?

The smartport for Catalyst 3750 does not have port role Diagnostic.

Is there a switch command for that purpose?

Should I use wireshark?

Cheers,

Pei Wai

[hobbe]

This is how i do capturing of traffic.

Configure an apropriate span port.

setup wireshark on a machine

connect the machine to the span port and start sniffing.

if you only want to know the ammount of traffic then you can use fx snmp to get the numbers of the interface you are interested in.

good luck

HTH

[Sandeep Choudhary]

Just Check this, Might be it helps.

http://forums.cacti.net/about29656.html&highlight=
http://www.experts-exchange.com/Hardware/Networking_Hardware/Switches/Q_23738165.html

Vlans on 3560s, 3750s and 3550s do not show stats.  The packets are forwarded with the ASIC chips and do not cross the CPU for actual processing.  To actually see the traffic you will need to turn off CEF, which decrases the performance significantly (not recommended, see links above).

Regards

Please rate if it helps.

[nkarthikeyan]

Hi,

for example you are monitoring ports fa0/1-3

say you are connecting your sniffer in fa0/4

int fastethernet 0/4 (connects with wireshark/ethreal/other sniffer)

port monitor FastEthernet0/1
port monitor FastEthernet0/2
port monitor FastEthernet0/3
port monitor vlan 
!

So this will monitor all the traffic will come to ports 1-3.

This differs for different device models.

Please do rate for the helpful ports.

By

Karthik