Audit log plugin¶

Percona Audit Log Plugin provides monitoring and logging of connection and query activity that were performed on specific server. Information about the activity is stored in a log file. This implementation is alternative to the MySQL Enterprise Audit Log Plugin

Version specific information¶

8.0.12-1: The feature was ported from Percona Server for MySQL 5.7.
Percona Server for MySQL 8.0.15-6: The Audit_log_buffer_size_overflow variable was implemented.

Install the plugin¶

The audit Log plugin is installed, but, by default, is not enabled when you install Percona Server for MySQL. To check if the plugin is enabled run the following commands:

mysql> SELECT * FROM information_schema.PLUGINS WHERE PLUGIN_NAME LIKE '%audit%';

Expected output

Empty set (0.00 sec)

mysql> SHOW variables LIKE 'audit%';

Expected output

Empty set (0.01 sec)

mysql> SHOW variables LIKE 'plugin%';

Expected output

+---------------+------------------------+
| Variable_name | Value                  |
+---------------+------------------------+
| plugin_dir    | /usr/lib/mysql/plugin/ |
+---------------+------------------------+
1 row in set (0.00 sec)

Note

The location of the MySQL plugin directory depends on the operating system and may be different on your system.

The following command enables the plugin:

mysql> INSTALL PLUGIN audit_log SONAME 'audit_log.so';

Run the following command to verify if the plugin was installed correctly:

mysql> SELECT * FROM information_schema.PLUGINS WHERE PLUGIN_NAME LIKE '%audit%'\G

Expected output

*************************** 1. row ***************************
        PLUGIN_NAME: audit_log
        PLUGIN_VERSION: 0.2
        PLUGIN_STATUS: ACTIVE
        PLUGIN_TYPE: AUDIT
PLUGIN_TYPE_VERSION: 4.1
        PLUGIN_LIBRARY: audit_log.so
PLUGIN_LIBRARY_VERSION: 1.7
        PLUGIN_AUTHOR: Percona LLC and/or its affiliates.
    PLUGIN_DESCRIPTION: Audit log
        PLUGIN_LICENSE: GPL
        LOAD_OPTION: ON
1 row in set (0.00 sec)

You can review the audit log variables with the following command:

mysql> SHOW variables LIKE 'audit%';

Expected output

+-----------------------------+---------------+
| Variable_name               | Value         |
+-----------------------------+---------------+
| audit_log_buffer_size       | 1048576       |
| audit_log_exclude_accounts  |               |
| audit_log_exclude_commands  |               |
| audit_log_exclude_databases |               |
| audit_log_file              | audit.log     |
| audit_log_flush             | OFF           |
| audit_log_format            | OLD           |
| audit_log_handler           | FILE          |
| audit_log_include_accounts  |               |
| audit_log_include_commands  |               |
| audit_log_include_databases |               |
| audit_log_policy            | ALL           |
| audit_log_rotate_on_size    | 0             |
| audit_log_rotations         | 0             |
| audit_log_strategy          | ASYNCHRONOUS  |
| audit_log_syslog_facility   | LOG_USER      |
| audit_log_syslog_ident      | percona-audit |
| audit_log_syslog_priority   | LOG_INFO      |
+-----------------------------+---------------+
18 rows in set (0.00 sec)

Log format¶

The plugin supports the following log formats: OLD, NEW, JSON, and CSV. The OLD\`format and the``NEWformat are based on XML. TheOLDformat defines each log record with XML attributes. TheNEW` format defines each log record with XML tags. The information logged is the same for all four formats. The audit_log_format variable controls the log format choice.

Format examples¶

The following formats are available:

Old log formatNew log formatJSON formatCSV format

<AUDIT_RECORD
NAME="Query"
RECORD="3_2021-06-30T11:56:53"
TIMESTAMP="2021-06-30T11:57:14 UTC"
COMMAND_CLASS="select"
CONNECTION_ID="3"
STATUS="0"
SQLTEXT="select * from information_schema.PLUGINS where PLUGIN_NAME like '%audit%'"
USER="root[root] @ localhost []"
HOST="localhost"
OS_USER=""
IP=""
DB=""
/>

<AUDIT_RECORD>
<NAME>Query</NAME>
<RECORD>16684_2021-06-30T16:07:41</RECORD>
<TIMESTAMP>2021-06-30T16:08:06 UTC</TIMESTAMP>
<COMMAND_CLASS>select</COMMAND_CLASS>
<CONNECTION_ID>2</CONNECTION_ID>
<STATUS>0</STATUS>
<SQLTEXT>select id, holder from one</SQLTEXT>
<USER>root[root] @ localhost []</USER>
<HOST>localhost</HOST>
<OS_USER></OS_USER>
<IP></IP>
<DB></DB>

{"audit_record":{"name":"Query","record":"13149_2021-06-30T15:03:11","timestamp":"2021-06-30T15:07:58 UTC","command_class":"show_databases","connection_id":"2","status":0,"sqltext":"show databases","user":"root[root] @ localhost []","host":"localhost","os_user":"","ip":"","db":""}}

"Query","22567_2021-06-30T16:10:09","2021-06-30T16:19:00 UTC","select","2",0,"select count(*) from one","root[root] @ localhost []","localhost","","",""

Audit log events¶

The audit Log plugin generates a log of following events.

AuditConnect or DisconnectQuery

Audit event indicates that audit logging started or finished. NAME field will be Audit when logging started and NoAudit when logging finished. Audit record also includes server version and command-line arguments.

??? example "Audit event"

    ```text
    <AUDIT_RECORD
    NAME="Audit"
    RECORD="1_2021-06-30T11:56:53"
    TIMESTAMP="2021-06-30T11:56:53 UTC"
    MYSQL_VERSION="5.7.34-37"
    STARTUP_OPTIONS="--daemonize --pid-file=/var/run/mysqld/mysqld.pid"
    OS_VERSION="x86_64-debian-linux-gnu"
    />
    ```

Connect record event will have NAME field Connect when user logged in or login failed, or Quit when connection is closed.

The additional fields for this event are the following:

* `CONNECTION_ID`

* `STATUS`

* `USER`

* `PRIV_USER`

* `OS_LOGIN`

* `PROXY_USER`

* `HOST`

* `IP`

The value for STATUS is 0 for successful logins and non-zero for failed logins.

Disconnect event

<AUDIT_RECORD
NAME="Quit"
RECORD="5_2021-06-29T19:33:03"
TIMESTAMP="2021-06-29T19:34:38Z"
CONNECTION_ID="14"
STATUS="0"
USER="root"
PRIV_USER="root"
OS_LOGIN=""
PROXY_USER=""
HOST="localhost"
IP=""
DB=""
/>

Additional fields for this event are: COMMAND_CLASS (values come from the com_status_vars array in the `sql/mysqld.cc`` file in a MySQL source distribution.

Examples are select, alter_table, create_table, etc.), CONNECTION_ID, STATUS (indicates an error when the vaule is non-zero), SQLTEXT (text of SQL-statement), USER, HOST, OS_USER, IP.

The possible values for the NAME name field for this event are Query, Prepare, Execute, Change user, etc.

Query event

<AUDIT_RECORD
NAME="Query"
RECORD="4_2021-06-29T19:33:03"
TIMESTAMP="2021-06-29T19:33:34Z"
COMMAND_CLASS="show_variables"
CONNECTION_ID="14"
STATUS="0"
SQLTEXT="show variables like 'audit%'"
USER="root[root] @ localhost []"
HOST="localhost"
OS_USER=""
IP=""
DB=""
/>

Stream the audit log to syslog¶

To stream the audit log to syslog you’ll need to set audit_log_handler variable to SYSLOG. To control the syslog file handler, the following variables can be used: audit_log_syslog_ident, audit_log_syslog_facility, and audit_log_syslog_priority These variables have the same meaning as appropriate parameters described in the syslog(3) manual.

Note

The actions for the variables: audit_log_strategy, audit_log_buffer_size, audit_log_rotate_on_size, audit_log_rotations are captured only with FILE handler.

Filter methods¶

You can filter the results by the following methods.

Filter by userFilter by SQL command typeFiltering by database

The filtering by user feature adds two new global variables: audit_log_include_accounts and audit_log_exclude_accounts to specify which user accounts should be included or excluded from audit logging.

Only one of these variables can contain a list of users to be either included or excluded, while the other must be NULL. If one of the variables is set to be not NULL (contains a list of users), the attempt to set another one fails. An empty string means an empty list.

Changes of audit_log_include_accounts and audit_log_exclude_accounts do not apply to existing server connections.

The filtering by SQL command type adds two new global variables: audit_log_include_commands and audit_log_exclude_commands to specify which command types should be included or excluded from audit logging.

Only one of these variables can contain a list of command types to be either included or excluded, while the other needs to be NULL. If one of the variables is set to be not NULL (contains a list of command types), the attempt to set another one will fail. An empty string is defined as an empty list.

If both the audit_log_exclude_commands variable and the audit_log_include_commands variable are NULL, all commands are logged.

The filtering by an SQL database is implemented by two global variables: audit_log_include_databases and audit_log_exclude_databases to specify which databases should be included or excluded from audit logging.

Only one of these variables can contain a list of databases to be either included or excluded, while the other needs to be NULL. If one of the variables is set to be not NULL (contains a list of databases), the attempt to set another one will fail. Empty string means an empty list.

If query is accessing any of databases listed in audit_log_include_databases, the query will be logged. If query is accessing only databases listed in audit_log_exclude_databases, the query will not be logged. CREATE TABLE statements are logged unconditionally.

Changes of audit_log_include_databases and audit_log_exclude_databases do not apply to existing server connections.

Filter examples¶

The following are examples of the different filters.

Filter by userFilter by SQL command typeFilter by database

The following example adds users who will be monitored:

mysql> SET GLOBAL audit_log_include_accounts = 'user1@localhost,root@localhost';

Expected output

Query OK, 0 rows affected (0.00 sec)

If you try to add users to both the include list and the exclude list, the server returns the following error:

mysql> SET GLOBAL audit_log_exclude_accounts = 'user1@localhost,root@localhost';

Expected output

ERROR 1231 (42000): Variable 'audit_log_exclude_accounts' can't be set to the value of 'user1@localhost,root@localhost'

To switch from filtering by included user list to the excluded user list or back, first set the currently active filtering variable to NULL:

mysql> SET GLOBAL audit_log_include_accounts = NULL;

Expected output

Query OK, 0 rows affected (0.00 sec)

mysql> SET GLOBAL audit_log_exclude_accounts = 'user1@localhost,root@localhost';

Expected output

Query OK, 0 rows affected (0.00 sec)

mysql> SET GLOBAL audit_log_exclude_accounts = "'user'@'host'";

Expected output

Query OK, 0 rows affected (0.00 sec)

mysql> SET GLOBAL audit_log_exclude_accounts = '''user''@''host''';

Expected output

Query OK, 0 rows affected (0.00 sec)

mysql> SET GLOBAL audit_log_exclude_accounts = '\'user\'@\'host\'';

Expected output

Query OK, 0 rows affected (0.00 sec)

To see which user accounts have been added to the exclude list, run the following command:

mysql> SELECT @@audit_log_exclude_accounts;

Expected output

+------------------------------+
| @@audit_log_exclude_accounts |
+------------------------------+
| 'user'@'host'                |
+------------------------------+
1 row in set (0.00 sec)

Account names from mysql.user table are logged in the audit log. For example when you create a user:

mysql> CREATE USER 'user1'@'%' IDENTIFIED BY '111';

Expected output

Query OK, 0 rows affected (0.00 sec)

When user1 connects from localhost, the user is listed:

<AUDIT_RECORD
NAME="Connect"
RECORD="2_2021-06-30T11:56:53"
TIMESTAMP="2021-06-30T11:56:53 UTC"
CONNECTION_ID="6"
STATUS="0"
USER="user1" ;; this is a 'user' part of account in 8.0
PRIV_USER="user1"
OS_LOGIN=""
PROXY_USER=""
HOST="localhost" ;; this is a 'host' part of account in 8.0
IP=""
DB=""
/>

To exclude user1 from logging in Percona Server for MySQL 8.0, set:

SET GLOBAL audit_log_exclude_accounts = 'user1@%';

The value can be NULL or comma separated list of accounts in form user@host or 'user'@'host' (if user or host contains comma).

The available command types can be listed by running:

mysql> SELECT name FROM performance_schema.setup_instruments WHERE name LIKE "statement/sql/%" ORDER BY name;

Expected output

+------------------------------------------+
| name                                     |
+------------------------------------------+
| statement/sql/alter_db                   |
| statement/sql/alter_db_upgrade           |
| statement/sql/alter_event                |
| statement/sql/alter_function             |
| statement/sql/alter_procedure            |
| statement/sql/alter_server               |
| statement/sql/alter_table                |
| statement/sql/alter_tablespace           |
| statement/sql/alter_user                 |
| statement/sql/analyze                    |
| statement/sql/assign_to_keycache         |
| statement/sql/begin                      |
| statement/sql/binlog                     |
| statement/sql/call_procedure             |
| statement/sql/change_db                  |
| statement/sql/change_master              |
...
| statement/sql/xa_rollback                |
| statement/sql/xa_start                   |
+------------------------------------------+
145 rows in set (0.00 sec)

You can add commands to the include filter by running:

mysql> SET GLOBAL audit_log_include_commands= 'set_option,create_db';

Create a database with the following command:

mysql> CREATE DATABASE sample;

Expected output

<AUDIT_RECORD>
<NAME>Query</NAME>
<RECORD>24320_2021-06-30T17:44:46</RECORD>
<TIMESTAMP>2021-06-30T17:45:16 UTC</TIMESTAMP>
<COMMAND_CLASS>create_db</COMMAND_CLASS>
<CONNECTION_ID>2</CONNECTION_ID>
<STATUS>0</STATUS>
<SQLTEXT>CREATE DATABASE sample</SQLTEXT>
<USER>root[root] @ localhost []</USER>
<HOST>localhost</HOST>
<OS_USER></OS_USER>
<IP></IP>
<DB></DB>
</AUDIT_RECORD>

To switch the command type filtering type from included type list to the excluded list or back, first reset the currently-active list to NULL:

mysql> SET GLOBAL audit_log_include_commands = NULL;

Expected output

Query OK, 0 rows affected (0.00 sec)

mysql> SET GLOBAL audit_log_exclude_commands= 'set_option,create_db';

Expected output

Query OK, 0 rows affected (0.00 sec)

A stored procedure has the call_procedure command type. All the statements executed within the procedure have the same type call_procedure as well.

To add databases to be monitored, run:

mysql> SET GLOBAL audit_log_include_databases = 'test,mysql,db1';

Expected output

Query OK, 0 rows affected (0.00 sec)

mysql> SET GLOBAL audit_log_include_databases= 'db1','db3';

Expected output

Query OK, 0 rows affected (0.00 sec)

If you you try to add databases to both include and exclude lists server will show you the following error:

mysql> SET GLOBAL audit_log_exclude_databases = 'test,mysql,db1';

Error message

ERROR 1231 (42000): Variable 'audit_log_exclude_databases can't be set to the value of 'test,mysql,db1'

To switch from filtering by included database list to the excluded one or back, first set the currently active filtering variable to NULL:

mysql> SET GLOBAL audit_log_include_databases = NULL;

Expected output

Query OK, 0 rows affected (0.00 sec)

mysql> SET GLOBAL audit_log_exclude_databases = 'test,mysql,db1';

Expected output

Query OK, 0 rows affected (0.00 sec)

System variables¶

`audit_log_strategy`¶

Option	Description
Command Line:	Yes
Scope:	Global
Dynamic:	No
Data type	String
Default value	ASYNCHRONOUS
Allowed values	`ASYNCHRONOUS`, `PERFORMANCE`, `SEMISYNCHRONOUS`, `SYNCHRONOUS`

This variable is used to specify the audit log strategy, possible values are:

ASYNCHRONOUS - (default) log using memory buffer, do not drop messages if buffer is full
PERFORMANCE - log using memory buffer, drop messages if buffer is full
SEMISYNCHRONOUS - log directly to file, do not flush and sync every event
SYNCHRONOUS - log directly to file, flush and sync every event

This variable has effect only when audit_log_handler is set to FILE.

`audit_log_file`¶

Option	Description
Command Line:	Yes
Scope:	Global
Dynamic:	No
Data type	String
Default value	audit.log

This variable is used to specify the filename that’s going to store the audit log. It can contain the path relative to the datadir or absolute path.

`audit_log_flush`¶

Option	Description
Command Line:	Yes
Scope:	Global
Dynamic:	Yes
Data type	String
Default value	OFF

When this variable is set to ON log file will be closed and reopened. This can be used for manual log rotation.

`audit_log_buffer_size`¶

Option	Description
Command Line:	Yes
Scope:	Global
Dynamic:	No
Data type	Numeric
Default value	1 Mb

This variable can be used to specify the size of memory buffer used for logging, used when audit_log_strategy variable is set to ASYNCHRONOUS or PERFORMANCE values. This variable has effect only when audit_log_handler is set to FILE.

`audit_log_exclude_accounts`¶

Option	Description
Command Line:	Yes
Scope:	Global
Dynamic:	Yes
Data type	String

This variable is used to specify the list of users for which Filtering by user is applied. The value can be NULL or comma separated list of accounts in form user@host or 'user'@'host' (if user or host contains comma). If this variable is set, then audit_log_include_accounts must be unset, and vice versa.

`audit_log_exclude_commands`¶

Option	Description
Command Line:	Yes
Scope:	Global
Dynamic:	Yes
Data type	String

This variable is used to specify the list of commands for which Filtering by SQL command type is applied. The value can be NULL or comma separated list of commands. If this variable is set, then audit_log_include_commands must be unset, and vice versa.

`audit_log_exclude_databases`¶

Option	Description
Command Line:	Yes
Scope:	Global
Dynamic:	Yes
Data type	String

This variable is used to specify the list of commands for which Filtering by database is applied. The value can be NULL or comma separated list of commands. If this variable is set, then audit_log_include_databases must be unset, and vice versa.

`audit_log_format`¶

Option	Description
Command Line:	Yes
Scope:	Global
Dynamic:	No
Data type	String
Default value	OLD
Allowed values	`OLD`, `NEW`, `CSV`, `JSON`

This variable is used to specify the audit log format. The audit log plugin supports four log formats: OLD, NEW, JSON, and CSV. OLD and NEW formats are based on XML, where the former outputs log record properties as XML attributes and the latter as XML tags. Information logged is the same in all four formats.

`audit_log_include_accounts`¶

Option	Description
Command Line:	Yes
Scope:	Global
Dynamic:	Yes
Data type	String

This variable is used to specify the list of users for which Filtering by user is applied. The value can be NULL or comma separated list of accounts in form user@host or 'user'@'host' (if user or host contains comma). If this variable is set, then audit_log_exclude_accounts must be unset, and vice versa.

`audit_log_include_commands`¶

Option	Description
Command Line:	Yes
Scope:	Global
Dynamic:	Yes
Data type	String

This variable is used to specify the list of commands for which Filtering by SQL command type is applied. The value can be NULL or comma separated list of commands. If this variable is set, then audit_log_exclude_commands must be unset, and vice versa.

`audit_log_include_databases`¶

Option	Description
Command Line:	Yes
Scope:	Global
Dynamic:	Yes
Data type	String

This variable is used to specify the list of commands for which Filtering by database is applied. The value can be NULL or comma separated list of commands. If this variable is set, then audit_log_exclude_databases must be unset, and vice versa.

`audit_log_policy`¶

Option	Description
Command Line:	Yes
Scope:	Global
Dynamic:	Yes
Data type	String
Default	ALL
Allowed values	`ALL`, `LOGINS`, `QUERIES`, `NONE`

This variable is used to specify which events should be logged. Possible values are:

ALL - all events will be logged
LOGINS - only logins will be logged
QUERIES - only queries will be logged
NONE - no events will be logged

`audit_log_rotate_on_size`¶

Option	Description
Command Line:	Yes
Scope:	Global
Dynamic:	No
Data type	Numeric
Default value	0 (don’t rotate the log file)

This variable is measured in bytes and specifies the maximum size of the audit log file. Upon reaching this size, the audit log will be rotated. The rotated log files are present in the same directory as the current log file. The sequence number is appended to the log file name upon rotation. For this variable to take effect, set the audit_log_handler variable to FILE.

`audit_log_rotations`¶

Option	Description
Command Line:	Yes
Scope:	Global
Dynamic:	No
Data type	Numeric
Default value	0

This variable is used to specify how many log files should be kept when audit_log_rotate_on_size variable is set to non-zero value. This variable has effect only when audit_log_handler is set to FILE.

`audit_log_handler`¶

Option	Description
Command Line:	Yes
Scope:	Global
Dynamic:	No
Data type	String
Default value	FILE
Allowed values	`FILE`, `SYSLOG`

This variable is used to configure where the audit log will be written. If it is set to FILE, the log will be written into a file specified by audit_log_file variable. If it is set to SYSLOG, the audit log will be written to syslog.

`audit_log_syslog_ident`¶

Option	Description
Command Line:	Yes
Scope:	Global
Dynamic:	No
Data type	String
Default value	percona-audit

This variable is used to specify the ident value for syslog. This variable has the same meaning as the appropriate parameter described in the syslog(3) manual.

`audit_log_syslog_facility`¶

Option	Description
Command Line:	Yes
Scope:	Global
Dynamic:	No
Data type	String
Default value	LOG_USER

This variable is used to specify the facility value for syslog. This variable has the same meaning as the appropriate parameter described in the syslog(3) manual.

`audit_log_syslog_priority`¶

Option	Description
Command Line:	Yes
Scope:	Global
Dynamic:	No
Data type	String
Default value	LOG_INFO

This variable is used to specify the priority value for syslog. This variable has the same meaning as the appropriate parameter described in the syslog(3) manual.

Status Variables¶

`Audit_log_buffer_size_overflow`¶

Option	Description
Scope:	Global
Data type	Numeric

The number of times an audit log entry was either dropped or written directly to the file due to its size being bigger than audit_log_buffer_size variable.

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Last update: 2023-09-27

Audit log plugin¶

Version specific information¶

Install the plugin¶

Log format¶

Format examples¶

Audit log events¶

Stream the audit log to syslog¶

Filter methods¶

Filter examples¶

System variables¶

audit_log_strategy¶

audit_log_file¶

audit_log_flush¶

audit_log_buffer_size¶

audit_log_exclude_accounts¶

audit_log_exclude_commands¶

audit_log_exclude_databases¶

audit_log_format¶

audit_log_include_accounts¶

audit_log_include_commands¶

audit_log_include_databases¶

audit_log_policy¶

audit_log_rotate_on_size¶

audit_log_rotations¶

audit_log_handler¶

audit_log_syslog_ident¶

audit_log_syslog_facility¶

audit_log_syslog_priority¶

Status Variables¶

Audit_log_buffer_size_overflow¶

Get expert help¶

`audit_log_strategy`¶

`audit_log_file`¶

`audit_log_flush`¶

`audit_log_buffer_size`¶

`audit_log_exclude_accounts`¶

`audit_log_exclude_commands`¶

`audit_log_exclude_databases`¶

`audit_log_format`¶

`audit_log_include_accounts`¶

`audit_log_include_commands`¶

`audit_log_include_databases`¶

`audit_log_policy`¶

`audit_log_rotate_on_size`¶

`audit_log_rotations`¶

`audit_log_handler`¶

`audit_log_syslog_ident`¶

`audit_log_syslog_facility`¶

`audit_log_syslog_priority`¶

`Audit_log_buffer_size_overflow`¶