Check WAN status for Peplink Balance 305 via SNMP

Project Notes

# This plugin will check the status of a WAN interface via SNMP the from a Peplink Balance 305.
#
# Requirements for Peplink:
# Model: Peplink Balance 305
# Firmware: 8.1.0
# Peplink configured with SNMP version 3 with MD5 authentication and DES privacy.
#
# Requirements for Nagios server:
# Nagios: nagioscore 4.4.5
# OS: CentOS 8.1
# MIB: WAN.mib
#
# Make sure that the script is fetiching the right DATA. You can test it with the following command:
#
# snmpwalk -m WAN -v 3 -l authPriv -u <snmp_user> -a MD5 -A "<md5 authentication>" -x DES -X "<des privacy>" -Oq <hostname> WAN::wanName
#
# Example of output of test command:
# WAN::wanName.0 "MY WAN1"
# WAN::wanName.1 "MY WAN PROVIDER 2"
# WAN::wanName.2 "ANOTHER WAN PROVIDER"
#
# You have to place the WAN.mib file in:
# /usr/share/snmp/mibs
#
# Get the WAN.mib file from:
# https://download.peplink.com/resources/balance_max_snmp_mib-8.1.0.zip
#
# SYNTAX: ./check_peplink_balance_305_wan_status_snmp.bash <hostname> <snmp_user> <md5 authentication> <des privacy> <wan_name>
#
# EXAMPLE ./check_peplink_balance_305_wan_status_snmp.bash 172.31.0.1 "peplinkDC1" "246e410e31c34fdfa" "856c5b77821dde_n" "Comcast"
#
#
# Created: 2021-08-11 Author : Cesar San