设置nginx开机自启动：

创建nginx启动命令脚本 /etc/init.d/nginx ：

参考：https://www.cnblogs.com/whatmiss/p/7091220.html
参考：https://www.nginx.com/resources/wiki/start/topics/examples/redhatnginxinit/
参考：https://www.cnblogs.com/mswangblog/p/6628161.html

注意修改以下两项配置：
nginx=”/usr/local/nginx/sbin/nginx”
NGINX_CONF_FILE=”/usr/local/nginx/conf/nginx.conf”

#! /bin/bash
# chkconfig: - 85 15
PATH=/usr/local/nginx
DESC="nginx daemon"
NAME=nginx
DAEMON=$PATH/sbin/$NAME
CONFIGFILE=$PATH/conf/$NAME.conf
PIDFILE=$PATH/logs/$NAME.pid
SCRIPTNAME=/etc/init.d/$NAME
set -e
[ -x "$DAEMON" ] || exit 0
do_start() {
$DAEMON -c $CONFIGFILE || echo -n "nginx already running"
}
do_stop() {
$DAEMON -s stop || echo -n "nginx not running"
}
do_reload() {
$DAEMON -s reload || echo -n "nginx can't reload"
}
case "$1" in
start)
echo -n "Starting $DESC: $NAME"
do_start
echo "."
;;
stop)
echo -n "Stopping $DESC: $NAME"
do_stop
echo "."
;;
reload|graceful)
echo -n "Reloading $DESC configuration..."
do_reload
echo "."
;;
restart)
echo -n "Restarting $DESC: $NAME"
do_stop
do_start
echo "."
;;
*)
echo "Usage: $SCRIPTNAME {start|stop|reload|restart}" >&2
exit 3
;;
esac
exit 0