When evaluating a MySQL system one of the first things to look at is the MySQL error log. This is defined by the log[_-]error variable in the MySQL Configuration file. Generally found like:
grep log.error /etc/my.cnf log_error=/var/lib/mysql/logs/mysql_error_log log-error=/var/lib/mysql/logs/mysql_error_log
It is possible to find multiple rows because this could be defined in the [mysqld] and [mysqld_safe] sections. It is also possible it is incorrectly defined twice in any given section.
Immediately I see a problem here, and the following describes why. If you look at this file name, in this case it’s actually found, but the file is empty.
$ ls -l /var/lib/mysql/logs/mysql_error_log -rw-r----- 1 mysql mysql 0 Feb 19 20:35 /var/lib/mysql/logs/mysql_error_log
An error log should never exist and be empty, because starting the instance producing messages. An error log could be empty because the system does …[Read more]