MYSQLMANAGER(8) MySQL Database System MYSQLMANAGER(8)
NAME
mysqlmanager - the MySQL Instance Manager
SYNOPSIS
mysqlmanager [options]
DESCRIPTION
mysqlmanager is the MySQL Instance Manager (IM). This program monitors and manages MySQL Database
Server instances. MySQL Instance Manager is available for Unix-like operating systems, and also on
Windows as of MySQL 5.0.13. It runs as a daemon that listens on a TCP/IP port. On Unix, it also
listens on a Unix socket file.
MySQL Instance Manager is included in MySQL distributions from version 5.0.3, and can be used in
place of the mysqld_safe script to start and stop one or more instances of MySQL Server. Because
Instance Manager can manage multiple server instances, it can also be used in place of the
mysqld_multi script. Instance Manager offers these capabilities:
Instance Manager can start and stop instances, and report on the status of instances.
Server instances can be treated as guarded or unguarded:
When Instance Manager starts, it starts each guarded instance. If the instance crashes,
Instance Manager detects this and restarts it. When Instance Manager stops, it stops the
instance.
A nonguarded instance is not started when Instance Manager starts or monitored by it. If the
instance crashes after being started, Instance Manager does not restart it. When Instance
Manager exits, it does not stop the instance if it is running.
Instances are guarded by default. An instance can be designated as nonguarded by including the
nonguarded option in the configuration file.
Instance Manager provides an interactive interface for configuring instances, so that the need to
edit the configuration file manually is reduced or eliminated.
Instance Manager provides remote instance management. That is, it runs on the host where you want
to control MySQL Server instances, but you can connect to it from a remote host to perform
instance-management operations.
The following sections describe MySQL Instance Manager operation in more detail.
MYSQL INSTANCE MANAGER COMMAND OPTIONS
The MySQL Instance Manager supports a number of command options. For a brief listing, invoke
mysqlmanager with the --help option. Options may be given on the command line or in the Instance
Manager configuration file. On Windows, the standard configuration file is my.ini in the directory
where Instance Manager is installed. On Unix, the standard file is /etc/my.cnf. To specify a
different configuration file, start Instance Manager with the --defaults-file option.
mysqlmanager supports the following options:
--help, -?
Display a help message and exit.
--angel-pid-file=file_name
The file in which the angel process records its process ID when mysqlmanager runs in daemon mode
(that is, when the --run-as-service option is given). The default filename is
mysqlmanager.angel.pid.
If the --angel-pid-file option is not given, the default angel PID file has the same name as the
PID file except that any PID file extension is replaced with an extension of .angel.pid. (For
example, mysqlmanager.pid becomes mysqlmanager.angel.pid.)
This option was added in MySQL 5.0.23.
--bind-address=IP
The IP address to bind to.
--default-mysqld-path=path
The pathname of the MySQL Server binary. This pathname is used for all server instance sections in
the configuration file for which no mysqld-path option is present. The default value of this
option is the compiled-in pathname, which depends on how the MySQL distribution was configured.
Example: --default-mysqld-path=/usr/sbin/mysqld
--defaults-file=file_name
Read Instance Manager and MySQL Server settings from the given file. All configuration changes
made by the Instance Manager will be written to this file. This must be the first option on the
command line if it is used, and the file must exist.
If this option is not given, Instance Manager uses its standard configuration file. On Windows,
the standard file is my.ini in the directory where Instance Manager is installed. On Unix, the
standard file is /etc/my.cnf.
--install
On Windows, install Instance Manager as a Windows service. The service name is MySQL Manager. This
option was added in MySQL 5.0.11.
--log=file_name
The path to the Instance Manager log file. This option has no effect unless the --run-as-service
option is also given. If the filename specified for the option is a relative name, the log file is
created under the directory from which Instance Manager is started. To ensure that the file is
created in a specific directory, specify it as a full pathname.
If --run-as-service is given without --log, the log file is mysqlmanager.log in the data
directory.
If --run-as-service is not given, log messages go to the standard output. To capture log output,
you can redirect Instance Manager output to a file:
mysqlmanager > im.log
--monitoring-interval=seconds
The interval in seconds for monitoring server instances. The default value is 20 seconds. Instance
Manager tries to connect to each monitored (guarded) instance using the non-existing
MySQL_Instance_Manager user account to check whether it is alive/not hanging. If the result of the
connection attempt indicates that the instance is unavailable, Instance Manager performs several
attempts to restart the instance.
Normally, the MySQL_Instance_Manager account does not exist, so the connection attempts by
Instance Manager cause the monitored instance to produce messages in its general query log similar
to the following:
Access denied for user 'MySQL_Instance_M'@'localhost' (using password: YES)
The nonguarded option in the appropriate server instance section disables monitoring for a particular
instance. If the instance dies after being started, Instance Manager will not restart it. Instance
Manager tries to connect to a nonguarded instance only when you request the instance's status (for
example, with the SHOW INSTANCES status.
See the section called "MYSQL SERVER INSTANCE STATUS MONITORING", for more information.
--passwd, -P
Prepare an entry for the password file, print it to the standard output, and exit. You can
redirect the output from Instance Manager to a file to save the entry in the file.
--password-file=file_name
The name of the file where the Instance Manager looks for users and passwords. On Windows, the
default is mysqlmanager.passwd in the directory where Instance Manager is installed. On Unix, the
default file is /etc/mysqlmanager.passwd.
--pid-file=file_name
The process ID file to use. On Windows, the default file is mysqlmanager.pid in the directory
where Instance Manager is installed. On Unix, the default is mysqlmanager.pid in the data
directory.
--port=port_num
The port number to use when listening for TCP/IP connections from clients. The default port number
(assigned by IANA) is 2273.
--print-defaults
Print the current defaults and exit. This must be the first option on the command line if it is
used.
--remove
On Windows, removes Instance Manager as a Windows service. This assumes that Instance Manager has
been run with --install previously. This option was added in MySQL 5.0.11.
--run-as-service
On Unix, daemonize and start an angel process. The angel process monitors Instance Manager and
restarts it if it crashes. (The angel process itself is simple and unlikely to crash.)
--socket=path
On Unix, the socket file to use for incoming connections. The default file is named
/tmp/mysqlmanager.sock. This option has no meaning on Windows.
--standalone
This option is used on Windows to run Instance Manager in standalone mode. You should specify it
when you start Instance Manager from the command line. This option was added in MySQL 5.0.13.
--user=user_name
On Unix, the username of the system account to use for starting and running mysqlmanager. This
option generates a warning and has no effect unless you start mysqlmanager as root (so that it can
change its effective user ID), or as the named user. It is recommended that you configure
mysqlmanager to run using the same account used to run the mysqld server. ("User" in this context
refers to a system login account, not a MySQL user listed in the grant tables.)
--version, -V
Display version information and exit.
--wait-timeout=N
The number of seconds to wait for activity on an incoming connection before closing it. The
default is 28800 seconds (8 hours).
This option was added in MySQL 5.0.19. Before that, the timeout is 30 seconds and cannot be
changed.
MYSQL INSTANCE MANAGER CONFIGURATION FILES
Instance Manager uses its standard configuration file unless it is started with a --defaults-file
option that specifies a different file. On Windows, the standard file is my.ini in the directory
where Instance Manager is installed. On Unix, the standard file is /etc/my.cnf. (Prior to MySQL
5.0.10, the MySQL Instance Manager read the same configuration files as the MySQL Server, including
/etc/my.cnf, ~/.my.cnf, and so forth.)
Instance Manager reads options for itself from the [manager] section of the configuration file, and
options for server instances from [mysqld] or [mysqldN] sections. The [manager] section contains any
of the options listed in the section called "MYSQL INSTANCE MANAGER COMMAND OPTIONS", except for
those specified as having to be given as the first option on the command line. Here is a sample
[manager] section:
# MySQL Instance Manager options section
[manager]
default-mysqld-path = /usr/local/mysql/libexec/mysqld
socket=/tmp/manager.sock
pid-file=/tmp/manager.pid
password-file = /home/cps/.mysqlmanager.passwd
monitoring-interval = 2
port = 1999
bind-address = 192.168.1.5
Each [mysqld] or [mysqldN] instance section specifies options given by Instance Manager to a server
instance at startup. These are mainly common MySQL Server options (see the section called "COMMAND
OPTIONS"). In addition, a [mysqldN] section can contain the options in the following list, which are
specific to Instance Manager. These options are interpreted by Instance Manager itself; it does not
pass them to the server when it attempts to start that server.
Warning
The Instance Manager-specific options must not be used in a [mysqld] section. If a server is started
without using Instance Manager, it will not recognize these options and will fail to start properly.
mysqld-path = path
The pathname of the mysqld server binary to use for the server instance.
nonguarded
This option disables Instance Manager monitoring functionality for the server instance. By
default, an instance is guarded: At Instance Manager start time, it starts the instance. It also
monitors the instance status and attempts to restart it if it fails. At Instance Manager exit
time, it stops the instance. None of these things happen for nonguarded instances.
shutdown-delay = seconds
The number of seconds Instance Manager should wait for the server instance to shut down. The
default value is 35 seconds. After the delay expires, Instance Manager assumes that the instance
is hanging and attempts to terminate it. If you use InnoDB with large tables, you should increase
this value.
Here are some sample instance sections:
[mysqld1]
mysqld-path=/usr/local/mysql/libexec/mysqld
socket=/tmp/mysql.sock
port=3307
server_id=1
skip-stack-trace
core-file
skip-bdb
log-bin
log-error
log=mylog
log-slow-queries
[mysqld2]
nonguarded
port=3308
server_id=2
mysqld-path= /home/cps/mysql/trees/mysql-5.0/sql/mysqld
socket = /tmp/mysql.sock5
pid-file = /tmp/hostname.pid5
datadir= /home/cps/mysql_data/data_dir1
language=/home/cps/mysql/trees/mysql-5.0/sql/share/english
log-bin
log=/tmp/fordel.log
STARTING THE MYSQL SERVER WITH MYSQL INSTANCE MANAGER
This section discusses how Instance Manager starts server instances when it starts. However, before
you start Instance Manager, you should set up a password file for it. Otherwise, you will not be able
to connect to Instance Manager to control it after it starts. For details about creating Instance
Manager accounts, see the section called "INSTANCE MANAGER USER AND PASSWORD MANAGEMENT".
On Unix, the mysqld MySQL database server normally is started with the mysql.server script, which
usually resides in the /etc/init.d/ directory. In MySQL 5.0.3, this script invokes mysqlmanager (the
MySQL Instance Manager binary) to start MySQL. (In prior versions of MySQL the mysqld_safe script is
used for this purpose.) Starting from MySQL 5.0.4, the behavior of the startup script was changed
again to incorporate both setup schemes. In version 5.0.4, the startup script uses the old scheme
(invoking mysqld_safe) by default, but one can set the use_mysqld_safe variable in the script to 0
(zero) to use the MySQL Instance Manager to start a server.
Starting with MySQL 5.0.19, you can use Instance Manager if you modify the my.cnf configuration file
by adding use-manager to the [mysql.server] section:
[mysql.server]
use-manager
When Instance Manager starts, it reads its configuration file if it exists to find server instance
sections and prepare a list of instances. Instance sections have names of the form [mysqld] or
[mysqldN], where N is an unsigned integer (for example, [mysqld1], [mysqld2], and so forth).
After preparing the list of instances, Instance Manager starts the guarded instances in the list. If
there are no instances, Instance Manager creates an instance named mysqld and attempts to start it
with default (compiled-in) configuration values. This means that the Instance Manager cannot find the
mysqld program if it is not installed in the default location. (Section 4.6, "Installation Layouts",
describes default locations for components of MySQL distributions.) If you have installed the MySQL
server in a non-standard location, you should create the Instance Manager configuration file.
Instance Manager also stops all guarded server instances when it shuts down.
The allowable options for [mysqldN] server instance sections are described in the section called
"MYSQL INSTANCE MANAGER CONFIGURATION FILES". In these sections, you can use a special
mysqld-path=path-to-mysqld-binary option that is recognized only by Instance Manager. Use this option
to let Instance Manager know where the mysqld binary resides. If there are multiple instances, it may
also be necessary to set other options such as datadir and port, to ensure that each instance has a
different data directory and TCP/IP port number. Section 10, "Running Multiple MySQL Servers on the
Same Machine", discusses the configuration values that must differ for each instance when you run
multiple instance on the same machine.
Warning
The [mysqld] instance section, if it exists, must not contain any Instance Manager-specific options.
The typical Unix startup/shutdown cycle for a MySQL server with the MySQL Instance Manager enabled is
as follows:
1. The /etc/init.d/mysql script starts MySQL Instance Manager.
2. Instance Manager starts the guarded server instances and monitors them.
3. If a server instance fails, Instance Manager restarts it.
4. If Instance Manager is shut down (for example, with the /etc/init.d/mysql stop command), it shuts
down all server instances.
INSTANCE MANAGER USER AND PASSWORD MANAGEMENT
The Instance Manager stores its user information in a password file. On Windows, the default is
mysqlmanager.passwd in the directory where Instance Manager is installed. On Unix, the default file
is /etc/mysqlmanager.passwd. To specify a different location for the password file, use the
--password-file option.
If the password file does not exist or contains no password entries, you cannot connect to the
Instance Manager.
Note
Any Instance Manager process that is running to monitor server instances does not notice changes to
the password file. You must stop it and restart it after making password entry changes.
Entries in the password file have the following format, where the two fields are the account username
and encrypted password, separated by a colon:
petr:*35110DC9B4D8140F5DE667E28C72DD2597B5C848
Instance Manager password encryption is the same as that used by MySQL Server. It is a one-way
operation; no means are provided for decrypting encrypted passwords.
Instance Manager accounts differ somewhat from MySQL Server accounts:
MySQL Server accounts are associated with a hostname, username, and password (see Section 6.1,
"MySQL Usernames and Passwords").
Instance Manager accounts are associated with a username and password only.
This means that a client can connect to Instance Manager with a given username from any host. To
limit connections so that clients can connect only from the local host, start Instance Manager with
the --bind-address=127.0.0.1 option so that it listens only to the local network interface. Remote
clients will not be able to connect. Local clients can connect like this:
shell> mysql -h 127.0.0.1 -P 2273
To generate a new entry, invoke Instance Manager with the --passwd option and append the output to
the /etc/mysqlmanager.passwd file. Here is an example:
shell> mysqlmanager --passwd >> /etc/mysqlmanager.passwd
Creating record for new user.
Enter user name: mike
Enter password: mikepass
Re-type password: mikepass
At the prompts, enter the username and password for the new Instance Manager user. You must enter the
password twice. It does not echo to the screen, so double entry guards against entering a different
password than you intend (if the two passwords do not match, no entry is generated).
The preceding command causes the following line to be added to /etc/mysqlmanager.passwd:
mike:*BBF1F551DD9DD96A01E66EC7DDC073911BAD17BA
MYSQL SERVER INSTANCE STATUS MONITORING
To monitor the status of each guarded server instance, the MySQL Instance Manager attempts to connect
to the instance at regular intervals using the MySQL_Instance_Manager@localhost user account with a
password of check_connection.
You are not required to create this account for MySQL Server; in fact, it is expected that it will
not exist. Instance Manager can tell that a server is operational if the server accepts the
connection attempt but refuses access for the account by returning a login error. However, these
failed connection attempts are logged by the server to its general query log (see Section 9.2, "The
General Query Log").
Instance Manager also attempts a connection to nonguarded server instances when you use the SHOW
INSTANCES or SHOW INSTANCE STATUS command. This is the only status monitoring done for nonguarded
instances.
Instance Manager knows if a server instance fails at startup because it receives a status from the
attempt. For an instance that starts but later crashes, Instance Manager receives a signal because it
is the parent process of the instance.
CONNECTING TO MYSQL INSTANCE MANAGER
After you set up a password file for the MySQL Instance Manager and Instance Manager is running, you
can connect to it. The MySQL client-server protocol is used to communicate with the Instance Manager.
For example, you can connect to it using the standard mysql client program:
shell> mysql --port=2273 --host=im.example.org --user=mysql --password
Instance Manager supports the version of the MySQL client-server protocol used by the client tools
and libraries distributed with MySQL 4.1 or later, so other programs that use the MySQL C API also
can connect to it.
MYSQL INSTANCE MANAGER COMMANDS
After you connect to MySQL Instance Manager, you can issue commands. The following general principles
apply to Instance Manager command execution:
Commands that take an instance name fail if the name is not a valid instance name.
Commands that take an instance name fail if the instance does not exist.
Instance Manager maintains information about instance configuration in an internal (in-memory)
cache. Initially, this information comes from the configuration file if it exists, but some
commands change the configuration of an instance. Commands that modify the configuration file fail
if the file does not exist or is not accessible to Instance Manager.
On Windows, the standard file is my.ini in the directory where Instance Manager is installed. On
Unix, the standard configuration file is /etc/my.cnf. To specify a different configuration file,
start Instance Manager with the --defaults-file option.
If a [mysqld] instance section exists in the configuration file, it must not contain any Instance
Manager-specific options (see the section called "MYSQL INSTANCE MANAGER CONFIGURATION FILES").
Therefore, you must not add any of these options if you change the configuration for an instance
named mysqld.
The following list describes the commands that Instance Manager accepts, with examples.
START INSTANCE instance_name
This command attempts to start an offline instance. The command is asynchronous; it does not wait
for the instance to start.
mysql> START INSTANCE mysqld4;
Query OK, 0 rows affected (0,00 sec)
STOP INSTANCE instance_name
This command attempts to stop an instance. The command is synchronous; it waits for the instance
to stop.
mysql> STOP INSTANCE mysqld4;
Query OK, 0 rows affected (0,00 sec)
SHOW INSTANCES
Shows the names and status of all loaded instances.
mysql> SHOW INSTANCES;
+---------------+---------+
| instance_name | status |
+---------------+---------+
| mysqld3 | offline |
| mysqld4 | online |
| mysqld2 | offline |
+---------------+---------+
SHOW INSTANCE STATUS instance_name
Shows status and version information for an instance.
mysql> SHOW INSTANCE STATUS mysqld3;
+---------------+--------+---------+
| instance_name | status | version |
+---------------+--------+---------+
| mysqld3 | online | unknown |
+---------------+--------+---------+
SHOW INSTANCE OPTIONS instance_name
Shows the options used by an instance.
mysql> SHOW INSTANCE OPTIONS mysqld3;
+---------------+---------------------------------------------------+
| option_name | value |
+---------------+---------------------------------------------------+
| instance_name | mysqld3 |
| mysqld-path | /home/cps/mysql/trees/mysql-4.1/sql/mysqld |
| port | 3309 |
| socket | /tmp/mysql.sock3 |
| pid-file | hostname.pid3 |
| datadir | /home/cps/mysql_data/data_dir1/ |
| language | /home/cps/mysql/trees/mysql-4.1/sql/share/english |
+---------------+---------------------------------------------------+
SHOW instance_name LOG FILES
The command lists all log files used by the instance. The result set contains the path to the log
file and the log file size. If no log file path is specified in the instance section of the
configuration file (for example, log=/var/mysql.log), the Instance Manager tries to guess its
placement. If Instance Manager is unable to guess the log file placement you should specify the
log file location explicitly by using a log option in the appropriate instance section of the
configuration file.
mysql> SHOW mysqld LOG FILES;
+-------------+------------------------------------+----------+
| Logfile | Path | Filesize |
+-------------+------------------------------------+----------+
| ERROR LOG | /home/cps/var/mysql/owlet.err | 9186 |
| GENERAL LOG | /home/cps/var/mysql/owlet.log | 471503 |
| SLOW LOG | /home/cps/var/mysql/owlet-slow.log | 4463 |
+-------------+------------------------------------+----------+
Log options are described in the section called "COMMAND OPTIONS".
SHOW instance_name LOG {ERROR | SLOW | GENERAL} size[,offset_from_end]
This command retrieves a portion of the specified log file. Because most users are interested in
the latest log messages, the size parameter defines the number of bytes to retrieve from the end
of the log. To retrieve data from the middle of the log file, specify the optional offset_from_end
parameter. The following example retrieves 21 bytes of data, starting 23 bytes before the end of
the log file and ending 2 bytes before the end:
mysql> SHOW mysqld LOG GENERAL 21, 2;
+---------------------+
| Log |
+---------------------+
| using password: YES |
+---------------------+
SET instance_name.option_name[=option_value]
This command edits the specified instance's configuration section to change or add instance
options. The option is added to the section is it is not already present. Otherwise, the new
setting replaces the existing one.
mysql> SET mysqld2.port=3322;
Query OK, 0 rows affected (0.00 sec)
Changes made to the configuration file do not take effect until the MySQL server is restarted. In
addition, these changes are not stored in the instance manager's local cache of instance settings
until a FLUSH INSTANCES command is executed.
UNSET instance_name.option_name
This command removes an option from an instance's configuration section.
mysql> UNSET mysqld2.port;
Query OK, 0 rows affected (0.00 sec)
Changes made to the configuration file do not take effect until the MySQL server is restarted. In
addition, these changes are not stored in the instance manager's local cache of instance settings
until a FLUSH INSTANCES command is executed.
FLUSH INSTANCES
This command forces Instance Manager reread the configuration file and to refresh internal
structures. This command should be performed after editing the configuration file. The command
does not restart instances.
mysql> FLUSH INSTANCES;
Query OK, 0 rows affected (0.04 sec)
FLUSH INSTANCES is deprecated and will be removed in MySQL 5.2.
COPYRIGHT
Copyright 1997-2007 MySQL AB
This documentation is NOT distributed under a GPL license. Use of this documentation is subject to
the following terms: You may create a printed copy of this documentation solely for your own personal
use. Conversion to other formats is allowed as long as the actual content is not altered or edited in
any way. You shall not publish or distribute this documentation in any form or on any media, except
if you distribute the documentation in a manner similar to how MySQL disseminates it (that is,
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provided however that the documentation is disseminated together with the software on the same
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whole or in part, in another publication, requires the prior written consent from an authorized
representative of MySQL AB. MySQL AB reserves any and all rights to this documentation not expressly
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Please email <docs@mysql.com> for more information.
SEE ALSO
For more information, please refer to the MySQL Reference Manual, which may already be installed
locally and which is also available online at http://dev.mysql.com/doc/
AUTHOR
MySQL AB (http://www.mysql.com/) This software comes with no warranty.
MySQL 5.0 07/04/2007 MYSQLMANAGER(8)
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