#+OPTIONS: ^:nil

* BPF testing packet size changes

Playing with increasing packet size with TC-BPF. Testing what happens when
sending packets larger that MTU out an interface.

* Notes loading BPF object

How to manually load TC program:

#+begin_src sh
export DEV=mlx5p1
tc qdisc del dev "$DEV" clsact # Also deletes all filters
tc qdisc add dev "$DEV" clsact
tc filter add dev "$DEV" pref 1 handle 1 egress bpf da obj tc_bpf_inc_pkt_size.o
tc filter show dev "$DEV" egress
#+end_src

Be *VERY* careful with =replace= command, it MUST have same =pref= +=handle=:

#+begin_src sh
tc filter replace dev "$DEV" pref 1 handle 1 egress bpf da obj tc_bpf_inc_pkt_size.o
#+end_src