ubuntu 下 nginx 自启动设置

在/etc/init.d下面创建nginx文件
cd /etc/init.d
sudo touch nginx
sudo chmod +x nginx
nginx内容：
#! /bin/sh
#
### BEGIN INIT INFO
# Provides:          nginx
# Required-Start:    $syslog $local_fs $remote_fs
# Required-Stop:     $syslog $local_fs $remote_fs
# Should-Start:      dbus avahi
# Should-Stop:       dbus avahi
# Default-Start:     2 3 4 5
# Default-Stop:      1
# Short-Description: Nginx Server
# Description:       Nginx
### END INIT INFO

PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/opt/nginx/sbin
DAEMON=/opt/nginx/sbin/nginx
NAME=nginx
DESC="Nginx Server"
PID_FILE=/opt/nginx/logs/nginx.pid
test -x $DAEMON || exit 0
RUN=yes
#RUN_AS_USER=root

#DAEMON_OPTS="-a $RUN_AS_USER"

set -e

case "$1" in
start)
echo -n "Starting $DESC: "
$DAEMON
echo "$NAME."
;;
stop)
echo -n "Stopping $DESC: "
$DAEMON -s stop
echo "$NAME."
;;
force-reload)
$DAEMON -s reload
echo "";;
restart)
echo -n "Restarting $DESC: "
$DAEMON -s  stop
sleep 1
$DAEMON  start
echo "$NAME."
;;
status)
if [ -s $PID_FILE ]; then
RUNNING=$(cat $PID_FILE)
if [ -d /proc/$RUNNING ]; then
if [ $(readlink /proc/$RUNNING/exe) = $DAEMON ]; then
echo "$NAME is running."
exit 0
fi
fi

# No such PID, or executables don't match
echo "$NAME is not running, but pidfile existed."
rm $PID_FILE
exit 1
else
rm -f $PID_FILE
echo "$NAME not running."
exit 1
fi
;;
*)
N=/etc/init.d/$NAME
echo "Usage: $N {start|stop|restart|force-reload}" >&2
exit 1
;;
esac

exit 0