You can also configure the servers to use custom logs, based on whatever criteria you decide. For more information about this and the Web server logs in general, see the product documentation: IBM HTTP Server for i5/OS http://publib.boulder.ibm.com/infocenter/iseries/v5r4/topic/rzaie/rzaieconfiglo gs.htm Apache HTTP Server http://httpd.apache.org/docs/2.0/logs.html 9.4 Troubleshooting Zend Core The log files for Zend Core are located in the /usr/local/Zend/Core/logs directory. There are two PHP logs: php_error_log: This log contains error messages for PHP scripts. ini_modifier_log: The configuration for Zend Core is stored in the php.ini file. Changes to this file (that is, the configuration) are logged in the ini_modifier_log file. You can check this log for recent changes to Zend Core that might affect your application. There are two logs for the internal Apache server located in the /usr/local/Zend/apache2/logs directory: access_log: This log contains a list of all accesses made to the server. It (depending on configuration) lists the requesting IP address; the type of request (GET, PUT); the resource (URL) requested; and the return codes.