NG_ETHER_ECHO(4)

📦 version 12.2, in debian bookworm, debian trixie, ubuntu jammy, ubuntu noble, ubuntu questing, ubuntu resolute, ubuntu stonking

💖 NG_ETHER_ECHO(4) — the netgraph ether_echo node type, bestie edition 💖

okay so this is a page from the Kernel Interfaces Manual (that's the 4 in NG_ETHER_ECHO(4), iykyk), and it's about the ng_ether_echo node type. she's tiny. she's simple. she is literally just here to yell back. let's get into it 🫶

✨ NAME ✨

ng_ether_echo — netgraph ether_echo node type

✨ SYNOPSIS ✨

#include <netgraph/ng_ether_echo.h>

that's it. that's the whole synopsis. no arguments, no flags, no drama. she just is 🌸

✨ DESCRIPTION ✨

so the ether_echo node type does one (1) thing and she does it with her whole chest: she reflects all data and control messages back to the sender. every single one. no notes. 💅

she also assumes — and this is the important part, she does not check — that the packet is an ethernet frame. she's trusting like that. 🙈 and before she echoes it back, she swaps the source and destination addresses. classic move. iconic behavior.

this node type is used for testing and debugging. that's her whole job. she's a test girlie. 🧚

✨ HOOKS ✨

an ether_echo node accepts any request to connect, regardless of the hook name — as long as the name is unique. so like. call your hook whatever you want bestie, she's not gonna gatekeep the name. she only cares that nobody else already took it. one name, one hook, periodt. 👑

✨ CONTROL MESSAGES ✨

this node type supports only the generic control messages.

any other control messages? reflected back to the sender. immediately. like a text you sent at 3am that you're now seeing again in the cold light of day 😭

✨ SHUTDOWN ✨

this node shuts down when:

  1. she receives a NGM_SHUTDOWN control message, or
  2. all hooks have been disconnected.

either one. that's the whole vibe check. when it's time, it's time 🦋

✨ SEE ALSO ✨

go read those too, they're the friend group. 🌈

✨ HISTORY ✨

the ng_ether_echo node type was implemented in FreeBSD 8.0. so she's been out here echoing since way back. a true veteran. a legend. 🔥

✨ AUTHORS ✨

Julian Elischer <julian@FreeBSD.org>

thank you julian for this little echo queen, we love her 💜

and that's the whole page bestie!! this one shipped out via Debian on December 24, 2008 — a lil christmas eve gift of a manpage, no cap 🎀 bye ily, go swap some addresses ✨

📦 where this page comes from