#!/bin/bash
# dnsreport.sh
# Check all DNS servers for my domains and verify SOA serial number.
# Written by FrankB@FrankB.us 08/27/07, last update 09/15/07

domain_list="domain1.com domain2.com domain3.com"
# list of domains to do DNS checks for seperated by SPACES

email=user@domain.invalid
# email address to send reports to

report=0
# 0=report only if NS doesn't respond or has out of date serial number
# 1=always mail report

################## no edits needed below here

echo "`date +%a` `date +%D` `date +%r` DNS check" > /tmp/dns-results$$
echo "Server:			Serial:" >> /tmp/dns-results$$
for domain in $domain_list; do
   master_server=`dig $domain soa | grep SOA | grep -v "^;" | awk '{print $5}'`
   master_serial=`dig @$master_server $domain soa | grep SOA | grep -v "^;" | awk '{print $7}'`
   dig @$master_server $domain ns | grep NS | grep -v "^;" | awk '{print $5}' > /tmp/ns-list$$
   echo "" >> /tmp/dns-results$$
   echo "Domain:	$domain" >> /tmp/dns-results$$
   for server in `cat /tmp/ns-list$$`; do
      echo -n " $server	" >> /tmp/dns-results$$
      serial=`dig @$server $domain soa | grep SOA | grep -v "^;" | awk '{print $7}'`
      if [ -z $serial ]; then 
	 report=1
         if [ -u /usr/bin/fping ]; then
            echo "no response, `fping $server`" >> /tmp/dns-results$$
         else
            echo "no response" >> /tmp/dns-results$$
         fi
      elif [ $master_serial = $serial ]; then
         echo $serial >> /tmp/dns-results$$
      else
         echo "$serial Out of Sync" >> /tmp/dns-results$$
	 report=1
      fi
   done
   /bin/rm -f /tmp/ns-list$$
done
if [ $report = 1 ]; then
   mutt -s "DNS check `date +%a` `date +%D` `date +%r`" $email < /tmp/dns-results$$
fi
/bin/rm -f /tmp/dns-results$$