502 Bad Gateway with PHP

Troubleshooting
1

My issue:
Loading a PHP file gives 502 Bad Gateway

How I encountered the problem:
I’m attempting to install PHP with NGINX. I’ve install PHP 8.1 and done what I think is the correct config, but i can’t reach index.php on the server. It gives a 502. If I hit index.html all is well.

Solutions I’ve tried:

apt install php-fpm php-mysql
I edited my .conf file.
completed a nginx -t which had no issues
restarted nginx

My config:

nginx 1.26.3
Ubuntu 22.04.5 LTS

my .conf for the domain:

server {
    location / {
        root   /var/www/html/<my folder>
 		try_files $uri $uri/ /index.php$is_args$args;
    }
    server_name  <domain name>;

    index index.php index.html index.htm;

	
    location ~ \.php$ {
            fastcgi_split_path_info ^(.+\.php)(/.+)$;
            fastcgi_pass unix:/var/run/php8.1-fpm.sock;
            fastcgi_index index.php;
            include fastcgi_params;
    }

    location ~ /\.ht {
             deny all;
    }
 (other stuff for port 443 ssl )
2

Hi,

is there any records in a file defined by the error_log directive?

I’d recommend to enable debug log feature, that may get more details about the issue.

Please read that document very carefully.

Hope that helps.

3

Can you confirm that php-fpm is running on the system and that it is using the same socket path as is defined in the NGINX config?