I'm very new to the networking world (most of my time is spent as a developer), so I could very well be missing something simple. TL;DR version: I get 'martian packet' errors on response traffic when ...
Is there a way to check for GRE Tunnels? I've heard spammers will use GRE tunnels to send mail from a central machine out of another and would like to check for possible GRE tunnels.
I setup a gre tunnel a cisco router and a Linux machine, the tunnel interface in the Linux box named pic. Well i have to forward traffic coming from cisco through the Linux box. the rules i've set in ...