interface_status

#! /usr/bin/env sh

# Query interface status of network devices.
#
# Copyright (C) 2012-2024 Erik Auerswald <auerswal@unix-ag.uni-kl.de>
#
# Copying and distribution of this file, with or without modification,
# are permitted in any medium without royalty provided the copyright
# notice and this notice are preserved.  This file is offered as-is,
# without any warranty.
#
# Usage: interface_status IP|NAME...
#
# Queries the specified devices for interface status and interface name via
# SNMP (using snmpwalk from Net-SNMP) using standard MIBs.
#
# Use snmp.conf (e.g. $HOME/.snmp/snmp.conf) to configure SNMP access.
# The script uses OID names, thus Net-SNMP needs to be configured to allow
# this. See snmp_config(4) and snmp.conf(4) man-pages.
#
# Currently tested with Enterasys Networks switches only.
#
# Version 2024-03-04-01

STATUS=$(mktemp ifOperStatus.$$.XXXXXX)
NAME=$(mktemp ifName.$$.XXXXXX)

trap 'rm -f "${STATUS}" "${NAME}"' 0

# Specify the snmpwalk executable to use.
# This can be overridden from the environment.
# 'snmpbulkwalk' is faster, but needs SNMPv2c or SNMPv3
# (you should always use SNMPv3).
# Comment the following line to disable use of 'snmpbulkwalk.'
SNMPWALK=${SNMPWALK:=snmpbulkwalk}
# Use 'snmpwalk' as executable, if SNMPWALK is not specified.
SNMPWALK=${SNMPWALK:=snmpwalk}

for SWITCH_IP in "$@"; do
  echo "Interface status on ${SWITCH_IP}:"

  { "${SNMPWALK}" "${SWITCH_IP}" \
    interfaces.ifTable.ifEntry.ifOperStatus | \
  sed 's/^.*\.\([0-9]*\) .* \([a-z]*\).*$/\1 \2/' | \
  sort > "${STATUS}"; } &


  { "${SNMPWALK}" "${SWITCH_IP}" \
    ifMIB.ifMIBObjects.ifXTable.ifXEntry.ifName | \
  sed 's/^.*\.\([0-9]*\) .* \([^ ]*\).*$/\1 \2/' | \
  sort > "${NAME}"; } &

  wait

  join "${NAME}" "${STATUS}" | sort -n | sed 's/^[0-9]* / /'
done

exit 0