18.104.22.168 Error Logging on Unix and Unix-Like Systems
On Unix and Unix-like systems, mysqld uses
--log-error option to
determine whether mysqld writes the error log
to the console or a file, and, if to a file, the file name:
--log-error is not given,
mysqld writes the error log to the
--log-error is given
without naming a file, mysqld writes the
error log to a file named
in the data directory.
--log-error is given to
name a file, mysqld writes the error log
to that file (with an
.err suffix added
if the name has no suffix), located under the data directory
unless an absolute path name is given to specify a different
--log-error is given in an
option file in a
mysqld_safe finds and uses the option,
and passes it to mysqld.
It is common for Yum or APT package installations to configure
an error log file location under
with an option like
log-error=/var/log/mysqld.log in a server
configuration file. Removing the file name from the option
file in the data directory to be used.
If the server writes the error log to the console, it sets the
log_error system variable to
stderr. Otherwise, the server writes the
error log to a file and sets
log_error to the file name.