HestiaCP - ALERT: pm.min spare servers(0) must be a positive value

Ошибка при запуске php-fpm:

# systemctl restart php5.6-fpm

вида

Feb 16 07:41:45 90459.ip-ns.net php-fpm5.6[22630]: [16-Feb-2021 07:41:45] ALERT: [pool site.com] pm.min_spare_servers(0) must be a positive value
Feb 16 07:41:45 90459.ip-ns.net php-fpm5.6[22630]: [16-Feb-2021 07:41:45] ERROR: failed to post process the configuration
Feb 16 07:41:45 90459.ip-ns.net php-fpm5.6[22630]: [16-Feb-2021 07:41:45] ERROR: FPM initialization failed
Feb 16 07:41:45 90459.ip-ns.net systemd[1]: php5.6-fpm.service: Main process exited, code=exited, status=78/n/a
Feb 16 07:41:45 90459.ip-ns.net systemd[1]: php5.6-fpm.service: Failed with result 'exit-code'.
Feb 16 07:41:45 90459.ip-ns.net systemd[1]: Failed to start The PHP 5.6 FastCGI Process Manager.

или

Feb 16 07:52:48 90459.ip-ns.net php-fpm5.6[24787]: [16-Feb-2021 07:52:48] ALERT: [pool site.com] pm.max_spare_servers(0) must be a positive value

означает, что в конфиге PHP-FPM не заданы переменные

pm.min_spare_servers
pm.max_spare_servers

Открываем два конфиг файла - шаблон и для конкретного сайта:

# vi /usr/local/hestia/data/templates/web/php-fpm/PHP-5_6.tpl
pm.min_spare_servers = 5
pm.max_spare_servers = 35
# vi /etc/php/5.6/fpm/pool.d/site.com.conf
pm.min_spare_servers = 5
pm.max_spare_servers = 35

и перезапускаем наши сервисы PHP-FPM + Apache:

# systemctl restart apache2 php5.6-fpm