p4debug

P4 simple forwarder with monitoring/debugging features

This application does nothing but forwards packets from port 0 to port 1 and vice versa. During forwarding, according to the settings defined by ifdef conditions in the source code, the packets are processed through several debugging tables. The idea was adopted from https://github.com/jafingerhut/p4-guide/tree/master/checksum

The debugging tables can be used to print out to stdout or to output file what header fields the P4 switch encounters. Without such debug tables, simple troubleshooting is a bit cumbersome as P4 does not have print statements.

Usage

Compile if necessary:

p4c-bm2-ss monitoring.p4 -o monitoring.json

Run

simple_switch -i 0@eno3 -i 1@eno4 monitoring.json --log-console

Here eno3 and eno4 are the interfaces I have on my machine. If you don't want to put log to the console, replace --log-console with --log-file my_log.log