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Let's assume I throw in a multiple port Ethernet card
into my Linux box -- beyond the interface I use now.
Would there be any software that I could use to put
the two interfaces inline with an existing cable run to
transparently gather packets on the wire? Since I do
not have a hub or managed switch that I can use for
doing the normal port monitoring setup. NICs are not
expensive, so it should be a quick/easy solution if the
software exists for doing such a configuration.
If traffic passes through either interface (proxy server / NAT) you can capture packets using tcpdump or wireshark.
What are you monitoring for? There may be a better solution.Quote:
Since I do
not have a hub or managed switch that I can use for
doing the normal port monitoring setup.
The traffic is passing between two standalone devices.Quote:
Originally Posted by anomie
Neither is Windows or Linux, so I can't login for sniffing.
In this instance, I want to watch the packets coming inQuote:
Originally Posted by anomie
from a cable modem to the router. There is debate on
whether the packets are even arriving at the router or if
the router is actually dropping / ignoring them.
And, yes, this is a dumb SOHO "router" so it's not a fancy
device that I would be able to login and run debug logging.
Then my advice is not going to apply. I don't know of any way for you two sniff traffic between a cable modem and a hardware router with your current setup.
If you want to describe the problem symptoms further, maybe someone can help.
In the interest of time, I think I'm going to just stick aQuote:
Originally Posted by anomie
laptop between the modem and router, attempt making
my connection and sniff the incoming packets. Although
I would still be interested to hear from anyone that may
have a suggestion for an "inline" sniffing configuration in
the event I need to do this in a situation where it's not
as easy as swapping out the machines.
I'm trying to setup a VPN server from a commodity device.Quote:
Originally Posted by anomie
The client says there's no incoming packets, so I'm trying
to verify the packets are reaching the router and that it's
not the router that's malfunctioning.
Although a router malfunctioning will be easier to resolve
than trying to convince the ISP to open any ports they're
blocking... :mrgreen: