NG_LMI(4)

🌸 NAME 🌸

okay so ng_lmi(4) — frame relay LMI protocol netgraph node type — is literally the main character of this Kernel Interfaces Manual page, and she is here to explain the frame relay LMI protocol netgraph node type to you bestie 💅

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🦋 SYNOPSIS 🦋

#include <sys/types.h>
#include <netgraph/ng_lmi.h>

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💖 DESCRIPTION 💖

the lmi node type is out here doing the frame relay LMI protocol, no cap. it supports the ITU Annex A, ANSI Annex D, and Group-of-four LMI types, and it also supports auto-detection of the LMI type ✨

to enable a specific LMI type, connect the corresponding hook (annexA, annexD, or group4) to DLCI 0 or 1023 of a ng_frame_relay(4) node. typically, Annex A and Annex D live on DLCI 0 while Group-of-four lives on DLCI 1023 🎀

to enable LMI type auto-detection, connect the auto0 hook to DLCI 0 and the auto1023 hook to DLCI 1023. the node will attempt to automatically determine which LMI type is running at the switch, and go into that mode 🦋

bestie, only one fixed LMI type, or auto-detection, can be active at any given time — pick a lane 💀

the NGM_LMI_GET_STATUS control message can be used at any time to query the current status of the LMI protocol and each DLCI channel. this node also supports the NGM_TEXT_STATUS control message 👑

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🎀 HOOKS 🎀

this node type supports the following hooks:

• annexA — ITU Annex A LMI hook.
• annexD — ANSI Annex D LMI hook.
• group4 — Group-of-four LMI hook.
• auto0 — Auto-detection hook for DLCI 0.
• auto1023 — Auto-detection hook for DLCI 1023.

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💅 CONTROL MESSAGES 💅

this node type supports the generic control messages, plus the following:

NGM_LMI_GET_STATUS

this command returns status information in a struct nglmistat:

#define NGM_LMI_STAT_ARYSIZE   (1024/8)

struct nglmistat {
  u_char  proto[12];    /* Active proto (same as hook name) */
  u_char  hook[12];     /* Active hook */
  u_char  fixed;        /* If set to fixed LMI mode */
  u_char  autod;        /* If currently auto-detecting */
  u_char  seen[NGM_LMI_STAT_ARYSIZE];   /* DLCIs ever seen */
  u_char  up[NGM_LMI_STAT_ARYSIZE];     /* DLCIs currently up */
};

NGM_TEXT_STATUS

this generic message gives you a human-readable version of the node status 💖

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🌀 SHUTDOWN 🌀

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

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🌈 SEE ALSO 🌈

• netgraph(4), ng_frame_relay(4), ngctl(8)
• ANSI T1.617-1991 Annex D.
• ITU-T Q.933 Digital Subscriber Signaling System No. 1 - Signaling Specification for Frame Mode Basic Call Control, Annex A.

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⭐ HISTORY ⭐

the ng_lmi node type was implemented in FreeBSD 4.0 🧚

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👑 AUTHORS 👑

Julian Elischer <julian@FreeBSD.org>

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okay bye bestie — this NG_LMI(4) moment was brought to you by Debian, dated November 13, 2012 💋✨