Why won't php-fpm start?

Question

PHP

[email protected]:/etc/php/7.4# systemctl status php7.4-fpm.service
● php7.4-fpm.service - The PHP 7.4 FastCGI Process Manager
     Loaded: loaded (/lib/systemd/system/php7.4-fpm.service; enabled; vendor preset: enabled)
     Active: failed (Result: exit-code) since Thu 2020-11-05 15:31:53 MSK; 7s ago
       Docs: man:php-fpm7.4(8)
    Process: 3791781 ExecStart=/usr/sbin/php-fpm7.4 --nodaemonize --fpm-config /etc/php/7.4/fpm/php-fpm.conf (code=exited, status=78)
    Process: 3791789 ExecStopPost=/usr/lib/php/php-fpm-socket-helper remove /run/php/php-fpm.sock /etc/php/7.4/fpm/pool.d/www.conf 74 (code=exited, status=0/SUCCESS)
   Main PID: 3791781 (code=exited, status=78)

Nov 05 15:31:53 Boyle systemd[1]: Starting The PHP 7.4 FastCGI Process Manager...
Nov 05 15:31:53 Boyle php-fpm7.4[3791781]: [05-Nov-2020 15:31:53] ERROR: Another FPM instance seems to already listen on /run/php/php7.4-fpm.sock
Nov 05 15:31:53 Boyle php-fpm7.4[3791781]: [05-Nov-2020 15:31:53] ERROR: FPM initialization failed
Nov 05 15:31:53 Boyle systemd[1]: php7.4-fpm.service: Main process exited, code=exited, status=78/CONFIG
Nov 05 15:31:53 Boyle systemd[1]: php7.4-fpm.service: Failed with result 'exit-code'.
Nov 05 15:31:53 Boyle systemd[1]: Failed to start The PHP 7.4 FastCGI Process Manager.

How can I fix the error

Another FPM instance seems to already listen on /run/php/php7.4-fpm.sock

Everything works fine on the other server though.

Answer 1

I suspect that due to the simultaneous launch of FasCGI and FPM