DevConf.CZ 2020

We all know the drill: plug in the Ethernet cable or connect to Wi-Fi, assign an IP address to the network interface and traffic starts flowing. Or not?
Linux offers numerous ways for packets to be dropped, stolen, redirected or even modified before they reach the expected network interface. Most people have heard at least about the firewall, known as 'iptables' in Linux. But that's by far not the only packet thief out there!
We'll cover them all. We'll look at the commands that can be used to inspect the thieves. And how to discover where the packets end up. Iptables, nftables, bpfilter, tc, XDP, DPDK, layered and virtual interfaces, network name spaces and more.
And by the way, did you know that many of this affects your outgoing packets, too?
The talk is useful for everyone who finds themselves debugging a random network connected machine. Or anyone just interested in what Linux can do. Only basic admin skills required.