topic Re: Interface query in Network Security

Interface query

mani1910 — Thu, 01 Jul 2021 07:19:38 GMT

I have an DMZ network which has 10 DMZ interfaces from DMZ1 to DMZ 10.

I want to packet capture for an ip address in DMZ network.[10.10.x.x]

I want to do a packet capture but am not sure through which interface my traffic is flowing.

is there any way to find in CLI which interface this ip will flow to the destination.

Re: Interface query

Rob Ingram — Thu, 01 Jul 2021 07:26:40 GMT

@mani1910

If you know the source interface and IP address, then you can run packet-tracer command, this will identify the egress interface and ultimately if the packet is allowed or denied.

If you run a packet capture you don't necessarily need to specify an interface, just filter on host addresses.

Re: Interface query

mani1910 — Thu, 01 Jul 2021 09:23:55 GMT

Yes thanks for the info Rob.

But i know only source address, not sure of the interface by which it is configured.

is there any way we can get the interface details for the particular source and destination.

Re: Interface query

Rob Ingram — Thu, 01 Jul 2021 09:31:58 GMT

@mani1910

You could run "show route 10.10.x.x" that will identify the interface.

You could run a packet capture filtering on the source, that will identify the source interface.