The PHP-FPM service is down with the following error in its log file (
/var/log/plesk-phpXX-fpm/error.login case of PHP shipped by Plesk, where XX is a PHP version;
/var/log/php7.0-fpm.login case of PHP by OS vendor):
ERROR: [pool example.com] the prefix '/var/www/vhosts/system/example.com' does not exist or is not a directory
ERROR: failed to post process the configuration
ERROR: FPM initialization failed
PHP configurations for domains were not updated after changing virtual hosts location or mounting the new disk.
Connect to the server using SSH.
Update PHP configuration using the following command:
# plesk bin php_settings -u