You can change it by application/config/config.php
. Please find below mention code and set your custom extension.
/*
|--------------------------------------------------------------------------
| Log File Extension
|--------------------------------------------------------------------------
|
| The default filename extension for log files. The default 'php' allows for
| protecting the log files via basic scripting, when they are to be stored
| under a publicly accessible directory.
|
| Note: Leaving it blank will default to 'php'.
|
*/
$config['log_file_extension'] = '';
You can also generate logs depends on your requirement as describe below.
/*
|--------------------------------------------------------------------------
| Error Logging Threshold
|--------------------------------------------------------------------------
|
| You can enable error logging by setting a threshold over zero. The
| threshold determines what gets logged. Threshold options are:
|
| 0 = Disables logging, Error logging TURNED OFF
| 1 = Error Messages (including PHP errors)
| 2 = Debug Messages
| 3 = Informational Messages
| 4 = All Messages
|
| You can also pass an array with threshold levels to show individual error types
|
| array(2) = Debug Messages, without Error Messages
|
| For a live site you'll usually only enable Errors (1) to be logged otherwise
| your log files will fill up very fast.
|
*/
$config['log_threshold'] = 1;
Set custom directory to save your log files.
/*
|--------------------------------------------------------------------------
| Error Logging Directory Path
|--------------------------------------------------------------------------
|
| Leave this BLANK unless you would like to set something other than the default
| application/logs/ directory. Use a full server path with trailing slash.
|
*/
$config['log_path'] = '';
This will be used to set the permissions to log files.
/*
|--------------------------------------------------------------------------
| Log File Permissions
|--------------------------------------------------------------------------
|
| The file system permissions to be applied on newly created log files.
|
| IMPORTANT: This MUST be an integer (no quotes) and you MUST use octal
| integer notation (i.e. 0700, 0644, etc.)
*/
$config['log_file_permissions'] = 0644;
This will be used to set date format for each log entry.
/*
|--------------------------------------------------------------------------
| Date Format for Logs
|--------------------------------------------------------------------------
|
| Each item that is logged has an associated date. You can use PHP date
| codes to set your own date formatting
|
*/
$config['log_date_format'] = 'Y-m-d H:i:s';
I hope this will help you.