# tail -f error_log

PHP Warning:  PHP Startup: Unable to load dynamic library '/usr/lib64/php/modules/pdo_mysql.so' - libmysqlclient.so.16: cannot open shared object file: No such file or directory in Unknown on line 0

[Fri May 26 19:33:13 2017] [notice] Apache/2.2.15 (Unix) DAV/2 PHP/5.3.3 configured -- resuming normal operations

[Fri May 26 19:44:17 2017] [notice] caught SIGTERM, shutting down

[Fri May 26 19:44:17 2017] [notice] suEXEC mechanism enabled (wrapper: /usr/sbin/suexec)

[Fri May 26 19:44:17 2017] [notice] Digest: generating secret for digest authentication ...

[Fri May 26 19:44:17 2017] [notice] Digest: done

PHP Warning:  PHP Startup: Unable to load dynamic library '/usr/lib64/php/modules/mysql.so' - libmysqlclient.so.16: cannot open shared object file: No such file or directory in Unknown on line 0

PHP Warning:  PHP Startup: Unable to load dynamic library '/usr/lib64/php/modules/mysqli.so' - libmysqlclient.so.16: cannot open shared object file: No such file or directory in Unknown on line 0

PHP Warning:  PHP Startup: Unable to load dynamic library '/usr/lib64/php/modules/pdo_mysql.so' - libmysqlclient.so.16: cannot open shared object file: No such file or directory in Unknown on line 0

[Fri May 26 19:44:17 2017] [notice] Apache/2.2.15 (Unix) DAV/2 PHP/5.3.3 configured -- resuming normal operations

# rpm -qf /usr/lib64/perl5/auto/DBD/mysql/mysql.so

perl-DBD-MySQL-4.013-3.el6.x86_64

# yum install perl-DBD-MySQL.x86_64

# /etc/init.d/httpd restart