- 184.108.40.206 Error Log Configuration
- 220.127.116.11 Default Error Log Destination Configuration
- 18.104.22.168 Error Event Fields
- 22.214.171.124 Types of Error Log Filtering
- 126.96.36.199 Priority-Based Error Log Filtering (log_filter_internal)
- 188.8.131.52 Rule-Based Error Log Filtering (log_filter_dragnet)
- 184.108.40.206 Error Logging in JSON Format
- 220.127.116.11 Error Logging to the System Log
- 18.104.22.168 Error Log Output Format
- 22.214.171.124 Error Log File Flushing and Renaming
This section discusses how to configure the MySQL server for logging of diagnostic messages to the error log. For information about selecting the error message character set and language, see Section 10.6, “Error Message Character Set”, and Section 10.12, “Setting the Error Message Language”.
The error log contains a record of mysqld startup and shutdown times. It also contains diagnostic messages such as errors, warnings, and notes that occur during server startup and shutdown, and while the server is running. For example, if mysqld notices that a table needs to be automatically checked or repaired, it writes a message to the error log.
Depending on error log configuration, error messages may also
populate the Performance Schema
error_log table, to provide an SQL
interface to the log and enable its contents to be queried. See
Section 126.96.36.199, “The error_log Table”.
If used to start mysqld,
mysqld_safe may write messages to the error
log. For example, when mysqld_safe notices
abnormal mysqld exits, it restarts
mysqld and writes a
restarted message to the error log.
The following sections discuss aspects of configuring error logging.