Simulate 502 & 504 on nginx

Question

Is there any way to simulate these errors? I created some custom files for it, but I want to be sure that are displayed correctly. I made different message for every vhost.

Thank you in advance.

Answer 1

You can setup a custom error page for every location block in your nginx.conf or a global error page for the site.

Example for a 502 error :

location /my_blog {
    error_page 502 = /502.html;
    return 502;
}

A global 502 error page :

server {
     listen 80;
     error_page  502  /502.html;

     location /test {
          return 502;
     }
}

You can even append standard error codes together to have a single page for several types of errors :

location /my_blog {
     error_page 500 502 503 504 = /server_error.html;
     ...
}

To redirect to a totally different server, assuming you had an upstream server named server2 defined in your http section:

upstream server2 {
     server 10.0.0.1:80;
}

server {
     ...

     location /my_blog {
         error_page 502 = @try_server2;
         return 502;
     }

     location @try_server2 {
         proxy_pass http://server2;
     }
}

The manual can give you more details (there might be some others useful examples on the web).