[j-nsp] Question about monitor traffic

[Jacob Gårder]

Thiago Drechsel wrote:
> 1. I've used "monitor traffic" on lo0, in order capture some traffic. I was
> trying to capture pings, protocol packets and other traffic destined to lo0.
> The problem is that I could not capture any packet!! Why this behaviour? I
> understand that I must be able to capture traffic on lo0, like I do in any
> other interface. Am I missing something?
> PS: There was no filter applied during the tests.


I don't think you can capture packets destined for lo0 from other boxes,
as they enter the router through an other interface and is forwarded to
the Routing-Engine directly, they will never enter or be be sent out on lo0.

The only traffic seen on lo0, would be localy generated traffic destined
to lo0. For example if you ping 127.0.0.1 or some other lo0-address from
the local router.

So to capture traffic destined for lo0, you will have to capture the
traffic on the incoming/outgoing interface. Where you can match on the
addresses of lo0, if you want. Note that you will never capture traffic
transiting the router, as those pakets never reaches the RE.


Cheers,
Jacob Gårder