Nginx configuration problems

Question

randomly my nginx config went bad. Yesterday my site was on just fine and today I get the 502 bad gateway. My sites enabled file looks like this

upstream myapp {
    server 0.0.0.0:3000;
}

server {
    listen   80 default;

    access_log /webservices/crawler/log/access.log;
    error_log /webservices/crawler/error.log;

    root   /webservices/crawler/public/;
    index  index.html;

    client_max_body_size 500M;

    location / {
        proxy_set_header  X-Real-IP  $remote_addr;
        proxy_set_header  X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header Host $http_host;
        proxy_redirect off;

        if (-f $request_filename/index.html) {
            rewrite (.*) $1/index.html;
            break;
        }

        if (-f $request_filename.html) {
            rewrite (.*) $1.html;
            break;
        }

        if (!-f $request_filename) {
            proxy_pass http://myapp;
            break;
        }
    }
}

"/etc/nginx/sites-enabled/default" 38L, 825C                                                                                   1,1           All

does anyone see what I need to change? Maybe my sites IP changed last night? I just have no idea and thank you to anyone that takes a look.

Answer 1

"502 bad gateway" answer means that there is an issue with "upstream" web server (second line in your config). Check Nginx error log and you will find a cause. It can be connection error, empty reply, etc.