ошибка apache 500 internal server error

[apache]

Здравствуйте коллеги! Помогите починить апач, по обращению к серверу на 80 порт появлеется ошибка 500 internal server error
Права на содерживое корневой директории 755. В error_log апач вот такие записи. Что не так?

[Wed Apr 13 18:45:12.305797 2016] [mpm_prefork:notice] [pid 1216] AH00170: caught SIGWINCH, shutting down gracefully
[Wed Apr 13 18:45:12.477948 2016] [core:warn] [pid 2852] AH00117: Ignoring deprecated use of DefaultType in line 140 of /etc/apache2/httpd.conf.
[Wed Apr 13 18:45:12.483871 2016] [mpm_prefork:notice] [pid 2852] AH00163: Apache/2.4.6 (Linux/SUSE) PHP/5.4.20 configured -- resuming normal operations
[Wed Apr 13 18:45:12.483898 2016] [core:notice] [pid 2852] AH00094: Command line: '/usr/sbin/httpd2-prefork -f /etc/apache2/httpd.conf -D SYSTEMD -D FOREGROUND'
[Wed Apr 13 18:45:22.224635 2016] [php5:error] [pid 2869] [client 192.17.113.54:56243] PHP Fatal error: Call to undefined function mysql_connect() in /srv/www/htdocs/includes/class_core.php on line 317