Port mirroring question

[Fredster]

Hi,

I am trying to mirror the traffic sent from my weatherstation (on router 1) to a website (Weather Underground), to a Raspberry PI (On router 2).

I found a website that shows how to mirror ALL traffic from router 1 to the IP of the Raspberry PI , using the following commands (Executed on Router 1):

iptables -I PREROUTING -t mangle -j ROUTE --gw 192.168.1.4 --tee
iptables -I POSTROUTING -t mangle -j ROUTE --gw 192.168.1.4 --tee

Unfortunately too much traffic gets sent to the Raspi's IP 192.168.1.4, flooding it an making it unreachable (Forcing me to stop the mirroring).

My question:

How can I modify the commands so that ONLY the outgoing traffic from the weather station to Weather Underground website gets forwarded to my PI (On router 2)

Any help is greatly appreciated!

Fredster

 

[ColinTaylor]

You don't give any details on "router 1" or "router 2", but try something like this:

iptables -t mangle -A PREROUTING  -s 192.168.1.99 -j ROUTE --tee --gw 192.168.1.4
iptables -t mangle -A POSTROUTING -d 192.168.1.99 -j ROUTE --tee --gw 192.168.1.4

Where 192.168.1.99 is the IP address of your weather station.

 

[Fredster]

You don't give any details on "router 1" or "router 2", but try something like this:

iptables -t mangle -A PREROUTING  -s 192.168.1.99 -j ROUTE --tee --gw 192.168.1.4
iptables -t mangle -A POSTROUTING -d 192.168.1.99 -j ROUTE --tee --gw 192.168.1.4

Where 192.168.1.99 is the IP address of your weather station.

Hi Colin!

Works like a charm! The PI is reachable again using these lines instead!

Thank you very much for your quick answer!

Fredster

 

[sfx2000]

You don't give any details on "router 1" or "router 2", but try something like this:

iptables -t mangle -A PREROUTING  -s 192.168.1.99 -j ROUTE --tee --gw 192.168.1.4
iptables -t mangle -A POSTROUTING -d 192.168.1.99 -j ROUTE --tee --gw 192.168.1.4

Where 192.168.1.99 is the IP address of your weather station.

Nice - not really port mirroring, but it gets the job done... and probably a better approach.