Script which checks if A and PTR records match in your zone files of bind server

check_A_and_PTR_records.sh

#!/bin/bash

data_dir=/var/named/chroot/var/named/data/
[[ -d $data_dir ]] || { echo 'Run me on master bind server, exiting'; exit 1; }

echo '###############################################'
echo 'Checking if all IP addresses have a PTR record'
echo 'and if that PTR matches with the A record'
echo '###############################################'
echo

ips=$(grep -roE "\b([0-9]{1,3}\.){3}[0-9]{1,3}\b" $data_dir | cut -d ':' -f2)

for ip in $ips;do

  # skip localhost
  [[ "$ip" =~ 127\..* ]] && continue

  # find PTR
  ptr_record=$(dig +short -x $ip)

  # skip root servers
  [[ "$ptr_record" =~ .*root-servers\.net\. ]] && continue

  # find A record of PTR
  a_record=$(dig +short $ptr_record)

  # skip IP addreeses with correct reverse record
  [[ "$ip" == "$a_record" ]] && continue

  echo "ip: $ip, ptr_record: $ptr_record"
done

echo
echo
echo '#################################################'
echo 'Checking if all PTR records have correct A record'
echo '#################################################'
echo

ptrs=$(grep -r PTR $data_dir | awk '{ print $4 }')
for ptr in $ptrs;do

  # skip localhost
  [[ "$ptr" == 'localhost.' ]] && continue

  # find A record of PTR
  a_record=$(dig +short $ptr)

  [[ "$a_record" == '' ]] && { echo "ptr: $ptr - missing A record"; continue; }
  # find PTR of A record
  ptr_record=$(dig +short -x $a_record)

  # skip IP addreeses with correct A record
  [[ "$ptr" == "$ptr_record" ]] && continue

  echo "ptr: $ptr, real_ptr: $ptr_record"

done