Check for internet on router or router host (eg proxmox) and reboot if cannot ping hosts

pingtest.sh

#!/bin/sh

#=====================================================================
# pingtest.sh
# -----------
# Inspiration: https://forum.netgate.com/topic/64563/pfsense-auto-reboot-script-when-google-is-unreachable/9
#
# Prep
#   mkdir -p /var/log/pingtest
#
# Setup logrotate
#   Create /etc/logrotate.d/pingtest.conf with contents:
#   /var/log/pingtest/* {
#     weekly
#     rotate 3
#     size 1M
#     compress
#     delaycompress
#  }
#
# Add Cron (every 5 mins)
#  */5 * * * * /root/pingtest.sh >/dev/null 2>&1
#=====================================================================

#=====================================================================
# USER SETTINGS

# Hosts to check
ALLDEST="google.com yahoo.com"

# Wait beetween failures
SLEEP_ON_FAIL=5

# Max failures
MAX_FAILS=2

# Uptime before kicking in
UPTIME_MINS=30

# Log file
LOGFILE=/var/log/pingtest/ping.log
#=====================================================================

# Abort if uptime less than 30 mins to avoid reboot loops
uptime=`awk '{print int($1/60)}' /proc/uptime`

if [ $uptime -le $UPTIME_MINS ]; then
    echo "Skipping pingtest until up for $UPTIME_MINS mins (current uptime $uptime mins)" >> $LOGFILE
    exit 0
fi

# Log when script ran.
echo "==== Pingtest - Time:" `date +%Y%m%d.%H%M%S` "- Uptime: $uptime mins ====" >> $LOGFILE

COUNT=1
while [ $COUNT -le $MAX_FAILS ]
do

    for DEST in $ALLDEST
    do
        echo "Pinging $DEST" >> $LOGFILE
        ping -c1 $DEST >/dev/null 2>/dev/null
        if [ $? -eq 0 ]
        then
            echo "Ping $DEST OK." >> $LOGFILE
            exit 0
        fi
    done

    echo "All pings Failed $COUNT times" >> $LOGFILE

    if [ $COUNT -ge $MAX_FAILS ]
    then
        echo `date +%Y%m%d.%H%M%S` "Max failures of $MAX_FAILS reached. Rebooting..." >> $LOGFILE
        /usr/sbin/shutdown -r now >> $LOGFILE
        exit 1
    else
        echo "Waiting $SLEEP_ON_FAIL seconds until next ping attempt" >> $LOGFILE
        sleep "$SLEEP_ON_FAIL"
    fi

    COUNT=`expr $COUNT + 1`
done