环境：centos7+php+mysql+openresty，目前测试 systemctl status openresty ,systemctl status php-fpm,systemctl status mysql 都 active，正常的状态。

目前：

ps -ef | grep php-fpm

root 3348 1 0 00:13 ? 00:00:05 php-fpm: master process (/etc/php-fpm.conf) apache 3351 3348 0 00:13 ? 00:00:00 php-fpm: pool www apache 3352 3348 0 00:13 ? 00:00:00 php-fpm: pool www apache 3353 3348 0 00:13 ? 00:00:00 php-fpm: pool www apache 3354 3348 0 00:13 ? 00:00:00 php-fpm: pool www apache 3355 3348 0 00:13 ? 00:00:00 php-fpm: pool www apache 3356 3348 0 00:13 ? 00:00:00 php-fpm: pool www apache 3357 3348 0 00:13 ? 00:00:00 php-fpm: pool www apache 3358 3348 0 00:13 ? 00:00:00 php-fpm: pool www root 18518 18497 0 23:32 pts/1 00:00:00 grep --color=auto php-fpm

netstat -an |grep 80

tcp 0 0 127.0.0.1:80 0.0.0.0:* LISTEN
unix 2 [ ACC ] STREAM LISTENING 28071 /var/lib/mysql/mysql.sock unix 3 [ ] STREAM CONNECTED 11800
unix 3 [ ] STREAM CONNECTED 11801 /run/systemd/journal/stdout

贴出自己的 nginx.conf 和 error.log 粘贴如下：

#user root; worker_processes 1;

#error_log logs/error.log; #error_log logs/error.log notice; #error_log logs/error.log info;

#pid logs/nginx.pid;

events { worker_connections 1024; }

http { include mime.types; default_type application/octet-stream;

#log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
#                  '$status $body_bytes_sent "$http_referer" '
#                  '"$http_user_agent" "$http_x_forwarded_for"';

#access_log  logs/access.log  main;

sendfile        on;
#tcp_nopush     on;

#keepalive_timeout  0;
keepalive_timeout  65;

client_max_body_size 8m;    #允许客户端请求的最大单文件字节数
client_body_buffer_size 2m;  #缓冲区代理缓冲用户端请求的最大字节

gzip  on;
#WAF
lua_shared_dict limit 50m;
lua_shared_dict guard_dict 100m;
lua_shared_dict dict_captcha 70m;
lua_package_path "/usr/local/openresty/nginx/conf/waf/?.lua";
init_by_lua_file "/usr/local/openresty/nginx/conf/waf/init.lua";
access_by_lua_file "/usr/local/openresty/nginx/conf/waf/access.lua";

server {
    listen       127.0.0.1;
    server_name  mywebsitedomain.com;

    #charset koi8-r;

    #access_log  logs/host.access.log  main;

    location / {
        root   html;
        index  index.php index.html index.htm;
    }

    #error_page  404              /404.html;

    # redirect server error pages to the static page /50x.html
    #
    error_page   500 502 503 504  /50x.html;
    location = /50x.html {
        root   html;
    }

    # proxy the PHP scripts to Apache listening on 127.0.0.1:80
    #
    #location ~ \.php$ {
    #    proxy_pass   http://127.0.0.1;
    #}

    # pass the PHP scripts to FastCGI server listening on 127.0.0.1:9000
    #
    location ~ \.php$ {
        root           html;
        fastcgi_pass   127.0.0.1:9000;
        fastcgi_index  index.php;
        fastcgi_param  SCRIPT_FILENAME  $document_root$fastcgi_script_name;
        include        fastcgi_params;
    }

    # deny access to .htaccess files, if Apache's document root
    # concurs with nginx's one
    #
    #location ~ /\.ht {
    #    deny  all;
    #}
}


# another virtual host using mix of IP-, name-, and port-based configuration
#
#server {
#    listen       8000;
#    listen       somename:8080;
#    server_name  somename  alias  another.alias;

#    location / {
#        root   html;
#        index  index.html index.htm;
#    }
#}


# HTTPS server
#
#server {
#    listen       443 ssl;
#    server_name  localhost;

#    ssl_certificate      cert.pem;
#    ssl_certificate_key  cert.key;

#    ssl_session_cache    shared:SSL:1m;
#    ssl_session_timeout  5m;

#    ssl_ciphers  HIGH:!aNULL:!MD5;
#    ssl_prefer_server_ciphers  on;

#    location / {
#        root   html;
#        index  index.html index.htm;
#    }
#}

}

/usr/local/openresty/nginx/logs/error.log

2018/06/26 21:27:10 [alert] 740#740: *7927 open socket #10 left in connection 12

2018/06/26 21:27:10 [alert] 740#740: *7926 open socket #3 left in connection 13

2018/06/26 21:27:10 [alert] 740#740: aborting

kmdd33

2018-06-30 23:33:48 +08:00

同意谢谢各位。在 stackoverflow 上面找到了答案：

解决步骤：

1.在 nginx.conf 中把 error_log and pid 前面的注释去掉。就像这样，方便得出正确的 error.log

user root;
worker_processes 1;

#error_log logs/error.log;
error_log logs/error.log debug;
#error_log logs/error.log info;

pid logs/nginx.pid;

2.http{}里面的 80 端口正确配置方式是：

listen 80;
listen [::]:80 default_server;

3.检查哪个 pid 占用了 80 端口：809 这个进程占用了 80 端口

# sudo netstat -tulpn | grep --color :80
tcp 0 0 127.0.0.1:80 0.0.0.0:* LISTEN 809/nginx: master p
[root@li1382-238 ~]# sudo kill -2 809 （这个命令很重要）
[root@li1382-238 ~]# sudo netstat -tulpn | grep --color :80
[root@li1382-238 ~]# openresty
[root@li1382-238 ~]# openresty -t

# netstat -antp 这个命令也可以查出来哪个端口占用了 80 端口。

然后重启：openresty

在线请教小伙伴：重启 openresty 后，站点突然打不开了， 502 bad gateway

ps -ef | grep php-fpm

netstat -an |grep 80