Nginx - Pass all 404 errors back to PHP-FPM for custom error page processing

Question

I know this has been asked a thousand times, but all of the answers I'm found simply don't work (for me or usually the original OP of those questions)... So, I'll try to explain the problem as best as I possibly can and hopefully we can get it working for me and for others who have asked before. My Nginx config (with lots of other irrelevant stuff removed) is as follows: ``` http { # Config from here removed server { listen 80; listen 443 ssl; server_name mydomain.co.uk; ssl_certificate /xxxxxxx.crt; ssl_certificate_key /xxxxxxx.key; # Custom error pages root /var/www/viovet_frontend; error_page 404 = /error404.php; # Any simple .php page location ~ \.php$ { root /var/www/xxxxxx; #index index.php index.html; include /etc/nginx/fastcgi.conf; fastcgi_pass phpfastcgiservers; include fastcgi_params; fastcgi_intercept_errors on; } # Lots more config and re-write rules here removed } upstream phpfastcgiservers { server xxxxx1:9001; server xxxxx2:9001; server xxxxx3:9001; fair; } } ``` All I…

Accepted Answer

I've finally worked most of it out. Thanks everyone for your tips and putting the time in to write answer.

The issue is that our `error404.php` was returning our error page with an 404 Not Found header too (using `header('HTTP/1.0 404 Not Found');`) and Nginx was then intercepting this error as `recursive_error_pages` is off (default) and it was showing its own 404 page. Switching off `fastcgi_intercept_errors` is the solution. If we remove the `header('HTTP/1.0 404 Not Found');` from the error file then we'd get the error but with a `200` which is obviously not what we want.

This does not, however, solve the problem of accessing a missing page which ends with `.php` (so it matches the location block as we are now getting back the standard PHP-FPM response to those of a 404 header with the body `File not found.`. I could use Nate's answer to get around this, but I'd rather not need to specify all the file names there. I'll look for another solution for this and post it here when I get one.

EDIT: A more full solution:

You need to intercept errors in your main php location block (`fastcgi_intercept_errors` is `on`) and then have another block for your error pages where you don't intercept them. See this config example:

```
    server {
            listen 80;
            listen 443 ssl;
            server_name mydomain.co.uk;

ssl_certificate /xxxxxxx.crt;
            ssl_certificate_key /xxxxxxx.key;

# Custom error pages
            recursive_error_pages off;
            error_page 404 = /http_errors/404.php;
            # error_page 500 501 502 503 504 = /error5xx.php; # Not sure about this yet!

# Any simple .php page
            location ~ \.php$ {
                    root /var/www/xxxxx;

include /etc/nginx/fastcgi.conf;
                    fastcgi_pass phpfastcgiservers;
                    include fastcgi_params;

fastcgi_intercept_errors on;
            }

# Handling error pages
            location ^~ /http_errors/ {
                    internal;

root /var/www/xxxxx;

include /etc/nginx/fastcgi.conf;
                    fastcgi_pass phpfastcgiservers;
                    include fastcgi_params;

fastcgi_intercept_errors off;
            }
}
```

This will mean that any of your PHP pages which return an HTTP status code of 404 will have their own content (if any) ignored and the content of your `/http_errors/404.php` file will be used instead.

Nginx - Pass all 404 errors back to PHP-FPM for custom error page processing

Solution

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