Setting domain name for AWS EC2 instance

ec2-sethost.sh

#!/bin/bash

HOSTNAME=$1
IPV4=`/usr/bin/curl -s http://169.254.169.254/latest/meta-data/local-ipv4`

# Set the host name
hostname $HOSTNAME
echo $HOSTNAME > /etc/hostname

# Add fqdn to hosts file
cat<<EOF > /etc/hosts
# This file is automatically genreated by ec2-hostname script
127.0.0.1 localhost
$IPV4 $HOSTNAME

# The following lines are desirable for IPv6 capable hosts
::1 ip6-localhost ip6-loopback
fe00::0 ip6-localnet
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters
ff02::3 ip6-allhosts
EOF

/etc/init.d/hostname restart