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Monitoring interface traffic

I'm using a solution to monitor the traffic passing through the interface
SWCORE connecting with my router.
The Linux machine (sniff) has two interfaces (eth0 and eth1)
Etho (manages the machine) connected to the interface to another interface g1/18
(Sniff) connected in g1/27.

Add the following command:

monitor session 2 source interface Gi1/48
monitor session 2 destination interface Gi1/27

But I don't capture nothing.

I show monitor out following:

Session 2
Type : Local Session
Source Ports :
Both : Gi1/48
Destination Ports : Gi1/27
Encapsulation : Native
Ingress : Disabled
Learning : Disabled

Do what doing wrong? Help me??

  • Network Management

Re: Monitoring interface traffic

try this  "monitor session 2 source interface Gi1/48 ?"

Doesn't if show an option to span ingoing, outgoing or both traffic directions?

I think you need both

Do you see traffic on the spanport Gi1/27 if you do a  "show interface Gi1/27"  ?

The counters should go up

The interface Eth0 should be in promiscuous mode to capture the traffic other then for its own mac address or broad/multicast