我已在我的 centos 7 服务器中成功部署 nginx 和 gunicorn ，但收到 502 Bad Gateway 错误消息。我正在使用 nginx / 1.12.2 。我已经检查了gunicorn和nginx的状态。
gunicorn状态
● deepagi.service - Gunicorn instance to serve deepagi
Loaded: loaded (/etc/systemd/system/deepagi.service; enabled; vendor preset: disabled)
Active: active (running) since Sat 2017-12-02 10:49:30 UTC; 41min ago
Main PID: 1829 (gunicorn)
CGroup: /system.slice/deepagi.service
├─1829 /root/deepagi/deepagienv/bin/python2 /root/deepagi/deepagienv/bin/gunicorn --workers 3 --bind unix:deepagi.sock -m 007 wsgi
├─1834 /root/deepagi/deepagienv/bin/python2 /root/deepagi/deepagienv/bin/gunicorn --workers 3 --bind unix:deepagi.sock -m 007 wsgi
├─1839 /root/deepagi/deepagienv/bin/python2 /root/deepagi/deepagienv/bin/gunicorn --workers 3 --bind unix:deepagi.sock -m 007 wsgi
└─1840 /root/deepagi/deepagienv/bin/python2 /root/deepagi/deepagienv/bin/gunicorn --workers 3 --bind unix:deepagi.sock -m 007 wsgi
Dec 02 10:49:30 DeepAGI systemd[1]: Started Gunicorn instance to serve deepagi.
Dec 02 10:49:30 DeepAGI systemd[1]: Starting Gunicorn instance to serve deepagi...
Dec 02 10:49:30 DeepAGI gunicorn[1829]: [2017-12-02 10:49:30 +0000] [1829] [INFO] Starting gunicorn 19.7.1
Dec 02 10:49:30 DeepAGI gunicorn[1829]: [2017-12-02 10:49:30 +0000] [1829] [INFO] Listening at: unix:deepagi.sock (1829)
Dec 02 10:49:30 DeepAGI gunicorn[1829]: [2017-12-02 10:49:30 +0000] [1829] [INFO] Using worker: sync
Dec 02 10:49:30 DeepAGI gunicorn[1829]: [2017-12-02 10:49:30 +0000] [1834] [INFO] Booting worker with pid: 1834
Dec 02 10:49:30 DeepAGI gunicorn[1829]: [2017-12-02 10:49:30 +0000] [1839] [INFO] Booting worker with pid: 1839
Dec 02 10:49:30 DeepAGI gunicorn[1829]: [2017-12-02 10:49:30 +0000] [1840] [INFO] Booting worker with pid: 1840
nginx状态
● nginx.service - The nginx HTTP and reverse proxy server
Loaded: loaded (/usr/lib/systemd/system/nginx.service; enabled; vendor preset: disabled)
Active: active (running) since Sat 2017-12-02 11:16:18 UTC; 14min ago
Main PID: 2317 (nginx)
CGroup: /system.slice/nginx.service
├─2317 nginx: master process /usr/sbin/nginx
└─2318 nginx: worker process
Dec 02 11:16:18 DeepAGI systemd[1]: Starting The nginx HTTP and reverse proxy server...
Dec 02 11:16:18 DeepAGI nginx[2312]: nginx: the configuration file /etc/nginx/nginx.conf syntax is ok
Dec 02 11:16:18 DeepAGI nginx[2312]: nginx: configuration file /etc/nginx/nginx.conf test is successful
Dec 02 11:16:18 DeepAGI systemd[1]: Failed to read PID from file /run/nginx.pid: Invalid argument
Dec 02 11:16:18 DeepAGI systemd[1]: Started The nginx HTTP and reverse proxy server.
但我在nginx状态下看到了这种错误消息
Dec 02 11:16:18 DeepAGI systemd[1]: Failed to read PID from file /run/nginx.pid: Invalid argument
如何解决这个问题？