ng_echo(4)

ng_echo4

Loopback netgraph node

Usage

#include <netgraph/ng_echo.h>

Overview

The echo node type reflects all data and control messages back to the sender. This node type is used for testing and debugging.

Hooks

A echo node accepts any request to connect, regardless of the hook name, as long as the name is unique.

Control messages

This node type supports only the generic control messages. Any other control messages are reflected back to the sender.

Shutdown

This node shuts down upon receipt of a NGM_SHUTDOWN control message, or when all hooks have been disconnected.

Releases

71 releases since FreeBSD 3.5-RELEASE; the text changed 37 times.

  1. 3.5–3.5.1
  2. 4.1–4.1.1
  3. 4.2–4.4
  4. 4.5–4.11
  5. 5.0–6.3
  6. 6.4
  7. 7.0
  8. 7.1
  9. 7.2
  10. 7.3
  11. 7.4
  12. 8.0
  13. 8.1
  14. 8.2
  15. 8.3
  16. 8.4
  17. 9.0
  18. 9.1
  19. 9.2
  20. 9.3
  21. 10.0
  22. 10.1
  23. 10.2
  24. 10.3
  25. 10.4
  26. 11.0
  27. 11.1
  28. 11.2
  29. 11.3
  30. 11.4
  31. 12.0
  32. 12.1
  33. 12.2
  34. 12.3
  35. 12.4
  36. 13.0–13.2
  37. 13.3–15.1
  38. 16.0

History

The ng_echo node type was implemented in FreeBSD 4.0.

Authors

Julian Elischer ⟨[email protected]⟩

From base 16.0-CURRENT-20261027-61c70dc16a79 in FreeBSD 16.0-CURRENT (2026-10-27). Parsed by carta from the page's mdoc source.