A Django application is running on the AWS instance, configured via gunicorn and nginx, it is running well for more than a year, but suddenly, I got 502 bad gateway error, then I saw the below mentioned message in the nginx error log,
2017/05/17 16:18:35 [error] 1040#0: *7460 connect() to unix:/home/ubuntu/webapps/myproject/myproject/myproject.sock failed (111: Connection refused) while connecting to upstream, client: xx.xxxx.xx.xxx, server: xx.xx.xx.xxx, request: "GET / HTTP/1.1", upstream: "http://unix:/home/ubuntu/webapps/myproject/myproject/myproject.sock:/", host: "xx.xx.xx.xxx", referrer: "http://xx.xx.xx.xxx"
my nginx configuration:
server {
client_max_body_size 200M;
listen 80;
listen [::]:80 ipv6only=on;
server_name xx.xx.xx.xxx;
listen 443 ssl;
ssl_certificate /etc/nginx/ssl/myserver.crt;
ssl_certificate_key /etc/nginx/ssl/myserver.key;
location = /favicon.ico { access_log off; log_not_found off; }
location /static/ {
root /home/ubuntu/webapps/myproject/myproject;
}
location / {
include proxy_params;
proxy_pass http://unix:/home/ubuntu/webapps/myproject/myproject/myproject.sock;
proxy_set_header X-Forwarded-Protocol $scheme;
}
if ($scheme = http){
return 301 https://xx.xx.xx.xxx$request_uri;
}
if ($http_host = pas-cash.com){
return 303 https://xx.xx.xx.xxx$request_uri;
}
}
my gunicorn.conf
description "Gunicorn application server handling myproject"
start on runlevel [6789]
stop on runlevel [!6789]
respawn
setuid ubuntu
setgid www-data
chdir /home/ubuntu/webapps/myproject/myproject
exec /home/ubuntu/webapps/myproject/venv/bin/gunicorn --workers 3 --bind unix:/home/ubuntu/webapps/myproject/myproject/myproject.sock myproject.wsgi:application
After that I restarted the nginx by following command
sudo service nginx restart
After restarting, the application is running well, I can't find what will be the specific reason behind this error, I googled it for this, but I got different types of answer but nothing suitable for me, can you guys please help me out for, why this happened, is there any thing missing in my configuration or what will the common/general reason behind this behavior. It will be very helpful for me, Thanks in advance.