dnsmasq dhcp fallback

dnsmasq-dhcp-fallback.sh

#!/usr/bin/env bash
ON_BACKUP=0

while true; do
    if netcat -zuvn 10.0.1.2 67 > /dev/null 2>&1 ; then
        if [[ $ON_BACKUP != false ]]; then
            echo "Switching to primary"
            ON_BACKUP=false
            service dnsmasq stop > /dev/null 2>&1
        fi
    else
        if [[ $ON_BACKUP != true ]]; then
            echo "Switching to backup"
            ON_BACKUP=true
            service dnsmasq start > /dev/null 2>&1
        fi
    fi
    sleep 10
done