The log_filter_internal
log filter component
implements a simple form of log filtering based on error event
priority and error code. To affect how
log_filter_internal
permits or suppresses
error, warning, and information events intended for the error
log, set the
log_error_verbosity
and
log_error_suppression_list
system variables.
log_filter_internal
is built in and enabled
by default. If this filter is disabled,
log_error_verbosity
and
log_error_suppression_list
have
no effect, so filtering must be performed using another filter
service instead where desired (for example, with individual
filter rules when using log_filter_dragnet
).
For information about filter configuration, see
Section 7.4.2.1, “Error Log Configuration”.
Events intended for the error log have a priority of
ERROR
, WARNING
, or
INFORMATION
. The
log_error_verbosity
system
variable controls verbosity based on which priorities to
permit for messages written to the log, as shown in the
following table.
log_error_verbosity Value | Permitted Message Priorities |
---|---|
1 | ERROR |
2 | ERROR , WARNING |
3 | ERROR , WARNING ,
INFORMATION |
If log_error_verbosity
is 2
or greater, the server logs messages about statements that are
unsafe for statement-based logging. If the value is 3, the
server logs aborted connections and access-denied errors for
new connection attempts. See
Section B.3.2.9, “Communication Errors and Aborted Connections”.
If you use replication, a
log_error_verbosity
value of
2 or greater is recommended, to obtain more information about
what is happening, such as messages about network failures and
reconnections.
If log_error_verbosity
is 2
or greater on a replica, the replica prints messages to the
error log to provide information about its status, such as the
binary log and relay log coordinates where it starts its job,
when it is switching to another relay log, when it reconnects
after a disconnect, and so forth.
There is also a message priority of SYSTEM
that is not subject to verbosity filtering. System messages
about non-error situations are printed to the error log
regardless of the
log_error_verbosity
value.
These messages include startup and shutdown messages, and some
significant changes to settings.
In the MySQL error log, system messages are labeled as “System”. Other log sinks might or might not follow the same convention, and in the resulting logs, system messages might be assigned the label used for the information priority level, such as “Note” or “Information”. If you apply any additional filtering or redirection for logging based on the labeling of messages, system messages do not override your filter, but are handled by it in the same way as other messages.
The
log_error_suppression_list
system variable applies to events intended for the error log
and specifies which events to suppress when they occur with a
priority of WARNING
or
INFORMATION
. For example, if a particular
type of warning is considered undesirable “noise”
in the error log because it occurs frequently but is not of
interest, it can be suppressed.
log_error_suppression_list
does not suppress messages with a priority of
ERROR
or SYSTEM
.
The
log_error_suppression_list
value may be the empty string for no suppression, or a list of
one or more comma-separated values indicating the error codes
to suppress. Error codes may be specified in symbolic or
numeric form. A numeric code may be specified with or without
the MY-
prefix. Leading zeros in the
numeric part are not significant. Examples of permitted code
formats:
ER_SERVER_SHUTDOWN_COMPLETE
MY-000031
000031
MY-31
31
For readability and portability, symbolic values are preferable to numeric values.
Although codes to be suppressed can be expressed in symbolic or numeric form, the numeric value of each code must be in a permitted range:
1 to 999: Global error codes that are used by the server as well as by clients.
10000 and higher: Server error codes intended to be written to the error log (not sent to clients).
In addition, each error code specified must actually be used
by MySQL. Attempts to specify a code not within a permitted
range or within a permitted range but not used by MySQL
produce an error and the
log_error_suppression_list
value remains unchanged.
For information about error code ranges and the error symbols and numbers defined within each range, see Section B.1, “Error Message Sources and Elements”, and MySQL 9.0 Error Message Reference.
The server can generate messages for a given error code at
differing priorities, so suppression of a message associated
with an error code listed in
log_error_suppression_list
depends on its priority. Suppose that the variable has a value
of 'ER_PARSER_TRACE,MY-010001,10002'
. Then
log_error_suppression_list
has these effects on messages for those codes:
Messages generated with a priority of
WARNING
orINFORMATION
are suppressed.Messages generated with a priority of
ERROR
orSYSTEM
are not suppressed.
The effect of
log_error_verbosity
combines
with that of
log_error_suppression_list
.
Consider a server started with these settings:
[mysqld]
log_error_verbosity=2 # error and warning messages only
log_error_suppression_list='ER_PARSER_TRACE,MY-010001,10002'
In this case,
log_error_verbosity
permits
messages with ERROR
or
WARNING
priority and discards messages with
INFORMATION
priority. Of the nondiscarded
messages,
log_error_suppression_list
discards messages with WARNING
priority and
any of the named error codes.
The log_error_verbosity
value of 2 shown in the example is also its default value,
so the effect of this variable on
INFORMATION
messages is as just described
by default, without an explicit setting. You must set
log_error_verbosity
to 3 if
you want
log_error_suppression_list
to affect messages with INFORMATION
priority.
Consider a server started with this setting:
[mysqld]
log_error_verbosity=1 # error messages only
In this case,
log_error_verbosity
permits
messages with ERROR
priority and discards
messages with WARNING
or
INFORMATION
priority. Setting
log_error_suppression_list
has no effect because all error codes it might suppress are
already discarded due to the
log_error_verbosity
setting.