Nginx 1.21 - 502 Bad Gateway with PHP-FPM and Unix Socket Configuration
I'm stuck on something that should probably be simple. I'm working with a 502 Bad Gateway behavior when trying to access my Nginx server set up to use PHP-FPM via a Unix socket... My server is running Ubuntu 20.04, and I've configured the Nginx server block as follows: ```nginx server { listen 80; server_name example.com; root /var/www/html; index index.php index.html; location / { try_files $uri $uri/ /index.php?$query_string; } location ~ \.php$ { include snippets/fastcgi-php.conf; fastcgi_pass unix:/run/php/php8.0-fpm.sock; fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name; include fastcgi_params; } } ``` I've verified that the `php8.0-fpm` service is running by executing `systemctl status php8.0-fpm`, which gives me the following output: ``` ● php8.0-fpm.service - The PHP 8.0 FastCGI Process Manager Loaded: loaded (/lib/systemd/system/php8.0-fpm.service; enabled; vendor preset: enabled) Active: active (running) ``` Additionally, I checked the socket file's existence and permissions: ```bash ls -l /run/php/php8.0-fpm.sock ``` Output: ``` srw-rw---- 1 www-data www-data 0 Oct 19 12:35 /run/php/php8.0-fpm.sock ``` The permissions seem correct for the `www-data` user, which Nginx runs under. I also tried increasing the timeout settings in the PHP-FPM configuration in `/etc/php/8.0/fpm/pool.d/www.conf`: ```ini request_terminate_timeout = 30s ``` After making these changes, I restarted both Nginx and PHP-FPM using: ```bash sudo systemctl restart nginx sudo systemctl restart php8.0-fpm ``` Despite these efforts, I'm still working with the 502 Bad Gateway behavior. I've checked the Nginx behavior log located at `/var/log/nginx/behavior.log`, and the last entry indicates: ``` 2023/10/19 12:37:45 [behavior] 12345#12345: *3 connect() to unix:/run/php/php8.0-fpm.sock failed (2: No such file or directory) while connecting to upstream, client: 192.168.1.100, server: example.com, request: "GET /index.php HTTP/1.1", upstream: "fastcgi://unix:/run/php/php8.0-fpm.sock:" ``` It seems like the socket file isn’t being created, or Nginx can’t find it, but I need to pinpoint the scenario. Any suggestions on what else I might be missing or how to further troubleshoot this situation? For context: I'm using Php on Linux. Has anyone else encountered this? My team is using Php for this microservice. What's the best practice here? For context: I'm using Php on Debian.