mysqlmanager
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
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you distribute the documentation in a manner similar to how MySQL
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that the documentation is disseminated together with the software on
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copies or use of this documentation, in whole or in part, in another
publication, requires the prior written consent from an authorized
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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)
