a bash script to install the new relic client.

install_app_new_relic_RPM_for_php.sh

#!/bin/bash -e

#
# Test for a reboot, if this is a reboot just skip this script.
#
if test "$RS_REBOOT" = "true" ; then
	logger -t RightScale "New Relic PHP Agent install, skipped on a reboot.";
	exit 0;
fi

# Check if agent is already installed
type newrelic-daemon >/dev/null 2>&1 && {
	logger -t RightScale "New Relic agent already installed. Aborting.";
	exit 0;
}

if [ "$RS_DISTRO" = "ubuntu" ]; then
	wget -O - http://download.newrelic.com/548C16BF.gpg | apt-key add -
	if [ ! -f /etc/apt/sources.list.d/newrelic.list ]; then
		echo deb http://apt.newrelic.com/debian/ newrelic non-free > /etc/apt/sources.list.d/newrelic.list
		apt-get update
	fi
	apt-get install -y newrelic-php5

elif [ "$RS_DISTRO" = "centos" ]; then
	os_version=`uname -m`
	if [ "$os_version" = "x86_64" ]; then
		rpm -Uvh http://yum.newrelic.com/pub/newrelic/el5/x86_64/newrelic-repo-5-3.noarch.rpm
	else
		rpm -Uvh http://yum.newrelic.com/pub/newrelic/el5/i386/newrelic-repo-5-3.noarch.rpm
	fi
	yum install -y newrelic-php5
fi

# Install without user input
NR_INSTALL_SILENT=1 NR_INSTALL_KEY=$NR_LICENSE_KEY /usr/bin/newrelic-install install

# Insert and uncomment the application name if given
if [ -n "$NR_APP_NAME" ]; then
  sed -e "s/\;newrelic\.appname\ \=\ \"PHP\ Application\"/newrelic\.appname\ \=\ \"$NR_APP_NAME\"/g" -i /etc/php.d/newrelic.ini
fi

# Reboot apache to take effect
if [ "$RS_DISTRO" = "ubuntu" ]; then
	service apache2 restart
elif [ "$RS_DISTRO" = "centos" ]; then
	service httpd restart
fi

logger -t RightScale "Installed New Relic PHP Module."

This was helpful, thank you.