Disclaimer: this is only a note for myself so I don't have to look for the answer anywhere else.

Once again I find myself configuring nginx to serve a small php app in an ubuntu instance. Following one of the thousands of articles about that I uses this pice of configuration: 

location ~ \.php$ {
    try_files $uri =404;
    fastcgi_split_path_info  ^(.+\.php)(/.+)$;
    fastcgi_index            index.php;
    fastcgi_pass             unix:/var/run/php/php7.4-fpm.sock;
    include                  fastcgi_params;
    fastcgi_param   PATH_INFO       $fastcgi_path_info;
    fastcgi_param   SCRIPT_FILENAME $document_root$fastcgi_script_name;
}

and this line in particular fastcgi_pass unix:/var/run/php/php7.4-fpm.sock; is responsible for generating this connect() to unix:/var/run/php/php7.4-fpm.sock failed error. I have dealt with this before and I kind of remember the solution I use in the past and it has to do with the port php-fpm is listening to. So I went online look for that and indeed the solution is as follows:


  • Edit your /etc/php/X.X/fpm/pool.d/www.conf file (replace X.X with the version of php you are using) and find the following line:
listen = /var/run/phpX.X-fpm.sock # (replace `X.X` with the version of php you are using)

change it to be:

listen = 127.0.0.1:9000

then go to your nginx config file and update it accordingly fastcgi_pass 127.0.0.1:9000.