#!/bin/bash

# path to hosts file
hostsFile="/etc/hosts"

# get old puppet hosts entry
oldIP=`cat ${hostsFile} | grep puppet | cut -d" " -f1`

# get new ip
newIP=`dig realm.mynetgear.com +short`

# check if newIP is different and change hosts entry
if [ ${newIP} != ${oldIP} ]; then
    echo "Updating hosts file" | logger
    sed -ie "/${oldIP}/d" "${hostsFile}";
    echo "${newIP} realm.mynetgear.com realm" >> ${hostsFile}
    echo "${newIP} puppet.realm.local puppet" >> ${hostsFile}
else
  echo "IP still up-to-date. Nothing to do, exiting." | logger
fi