Network Availability Listing Logger

nall

#!/bin/bash
shopt -s -o nounset

#########################
# Trap exit to display end time
trap ctrl_c INT SIGINT
trap display_stats SIGUSR1

# Display stats on exit
function ctrl_c() {
	echo
	end_date=$(date)
	log_info "===== Finished nall at ${end_date} ===== "
	start_s=$(date -d "${start_date}" +%s)
	end_s=$(date -d "${end_date}" +%s)
	log_info "Ran for $(( (end_s - start_s) )) seconds"

	display_stats

	exit 0
}

#########################
# Variables
declare -a labels
declare -a ipaddresses
declare -a statuses
declare -a prevstatuses

# Color Codes
RED='\E[31;49m'
GREEN='\E[32;49m'
DEFAULT='\E[00;49m'

CONF_DIR=~/.nall
CONF_FILE=${CONF_DIR}/nall.conf

LOGGING=enabled
LOGFILE=${CONF_DIR}/nall-results.log

VERBOSITY=0

labels=(      " Home  DHCP " " Gateway IP " "  Modem IP  "  "   Cox IP   " " Google DNS " )
ipaddresses=( "192.168.0.10" "192.168.0.1"  "192.168.100.1" "68.10.8.165"  "8.8.8.8" )
statuses=()
prevstatuses=()
offline_count=()
total_count=()

SLEEP_INTERVAL=1
temp_sleep=$SLEEP_INTERVAL

#########################
# Functions

# Ensure CONF_DIR exists and all arrays are initialized
init() {
	if [[ ! -d "${CONF_DIR}" ]]; then
		mkdir -p "${CONF_DIR}"
	fi
	if [[ -e "$LOGFILE" ]]; then
		cat "$LOGFILE" >> "${LOGFILE}.archive"
		rm -f "$LOGFILE"
	fi

	# Set offline/total counts to 0 to start
	for ((i = 0; i < ${#ipaddresses[@]}; i++)); do
		offline_count[$i]=0
		total_count[$i]=0
		statuses[$i]="INIT"
		prevstatuses[$i]="INIT"
	done
}

# Allow for log data to be displayed if required
log_info() {
	echo "$*" >> $LOGFILE
	[[ $VERBOSITY -gt 0 ]] && echo "$*"
}

# Display a header row of all nodes to status
display_headers() {
	IFS='%'
	clear
	echo -e "Testing every ${temp_sleep}s:    ($(date))\n"

	for label in "${labels[@]}"; do
		echo -e "|${label}\c"
	done
	echo "|"
	unset IFS
}

# output packet status to log file
display_stats() {
	for ((i = 0; i < ${#ipaddresses[@]}; i++)); do
		local packet_loss=$(echo "scale=2; ${offline_count[$i]} / ${total_count[$i]} * 100" | bc -l)
		log_info "${labels[$i]} offline for ${offline_count[$i]} / ${total_count[$i]} packets (${packet_loss}% loss)"
	done
}

query_servers() {
	for ((i = 0; i < ${#ipaddresses[@]}; i++)); do
		prevstatuses[$i]=${statuses[$i]}
		
		ping "${ipaddresses[$i]}" -W 1 -c 1 > /dev/null 2>&1
		ping_status=$?
		
		if [[ ${ping_status} -eq 0 ]]; then
			statuses[$i]="up"
		else
			statuses[$i]="down"
			((offline_count[i]++))
		fi
		((total_count[i]++))
		
		if [[ $LOGGING == "enabled" ]]; then
			if [[ "${prevstatuses[$i]}" != "${statuses[$i]}" ]] && \
			   [[ "${prevstatuses[$i]}" != "INIT" ]]; then
				log_info "$(date): Host ${labels[$i]} changed from ${prevstatuses[$i]} to ${statuses[$i]}"
			fi
		fi
	done
}

display_status() {
	local returnstatus=0
	for ((i = 0; i < ${#statuses[@]}; i++)); do
		status=${statuses[$i]}
		if [[ "${status}" == "up" ]]; then
			echo -en "|     ${GREEN}up${DEFAULT}     "
		elif [[ "${status}" == "down" ]]; then
			echo -en "|    ${RED}down${DEFAULT}    "
			returnstatus=1
		else
			echo -en "|    ${RED}UNKN${DEFAULT}    "
			returnstatus=1
		fi
	done
	
	echo -en "|\r"
	
	return $returnstatus
}

version() {
	cat <<-_EOF
	#########################
	# Network Availability Listing Logger
	v1.01
	_EOF
}

usage() {
	version
	cat <<-_EOF
	Usage: null
		-d|--dir        Change nall directory
		--geometry
		-h|--help
		-l|--list       List program defaults
		--logging       Enable logging (default)
		--no-logging    Do not do logging
		-s|--sleep      Update sleep interval   
		-v|--verbose
		--list-domains  List of domains to monitor
		-?              Use defaults
	_EOF
}

#########################
# Parse Arguments

while [[ $# -gt 0 ]]; do
	# Parse through arguments
	case "$1" in
		-d|--dir)	CONF_DIR="$2"
				shift
				;;
		-h|--help)	usage
				exit 1
				;;
		--list)		echo "LOGGING: $LOGGING"
				echo "VERBOSITY: $VERBOSITY"
				echo "SLEEP_INTERVAL: $SLEEP_INTERVAL"
				exit 0
				;;
		--list-domains)	for ((i = 0; i < ${#ipaddresses[@]}; i++)); do
					echo "* ${labels[$i]}: ${ipaddresses[$i]}"
				done
				exit 0
				;;
		--logging)	LOGGING=enabled
				;;
		--no-logging)	LOGGING=disabled
				;;
		-s|--sleep)	SLEEP_INTERVAL="$2"
				shift
				;;
		-v|--verbose)	VERBOSITY=1
				;;
		-vv)		set -x
				;;
	esac
	shift
done

#########################
# Main

init

# Display headers
start_date=$(date)
log_info "===== Started nall at ${start_date} ===== "

while true; do
	query_servers
	
	display_headers
	
	display_status
	
	# If any board is offline, only sleep for 1 second to know when it comes back online.
	# Otherwise, sleep at the user defined interval
	if [[ $? -eq 0 ]]; then
		temp_sleep=${SLEEP_INTERVAL}
	else
		temp_sleep=1
	fi
	
	sleep ${temp_sleep}
done

exit