NAME
mysqlmanager - the MySQL Instance Manager
SYNOPSIS
mysqlmanager [options]
DESCRIPTION
Important
MySQL Instance Manager has been deprecated and is removed in MySQL
5.5.
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, as well as Windows. 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 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:
o Instance Manager can start and stop instances, and report on the
status of instances.
o Server instances can be treated as guarded or unguarded:
o 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.
o 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.
o Instance Manager provides an interactive interface for
configuring instances, so that the need to edit the
configuration file manually is reduced or eliminated.
o 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
Important
MySQL Instance Manager has been deprecated and is removed in MySQL
5.5.
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. The options for managing
entries in the password file are described further in the section
called "INSTANCE MANAGER USER AND PASSWORD MANAGEMENT".
o --help, -?
Display a help message and exit.
o --add-user
Add a new user (specified with the --username option) to the
password file. This option was added in MySQL 5.1.12.
o --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 file name 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 5.1.11.
o --bind-address=IP
The IP address to bind to.
o --check-password-file
Check the validity and consistency of the password file. This
option was added in MySQL 5.1.12.
o --clean-password-file
Drop all users from the password file. This option was added in
MySQL 5.1.12.
o --debug=debug_options, -# debug_options
Write a debugging log. A typical debug_options string is
'd:t:o,file_name'. This option was added in MySQL 5.1.10.
o --default-mysqld-path=path
The path name of the MySQL Server binary. This path name 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 path name, which depends on how the MySQL
distribution was configured. Example:
--default-mysqld-path=/usr/sbin/mysqld
o --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.
o --drop-user
Drop a user (specified with the --username option) from the
password file. This option was added in MySQL 5.1.12.
o --edit-user
Change an entry for an existing user (specified with the --username
option) in the password file. This option was added in MySQL
5.1.12.
o --install
On Windows, install Instance Manager as a Windows service. The
service name is MySQL Manager.
o --list-users
List the users in the password file. This option was added in MySQL
5.1.12.
o --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
file name 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 path name.
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
o --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 nonexisting
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.
o --mysqld-safe-compatible
Run in a mysqld_safe-compatible manner. For details, see the
section called "STARTING THE MYSQL SERVER WITH MYSQL INSTANCE
MANAGER". This option was added in MySQL 5.1.12.
o --password=password, -p password
Specify the password for an entry to be added to or modified in the
password file. Unlike the --password/-P option for most MySQL
programs, the password value is required, not optional. See also
the section called "INSTANCE MANAGER USER AND PASSWORD MANAGEMENT".
This option was added in MySQL 5.1.12.
o --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. See also the section called
"INSTANCE MANAGER USER AND PASSWORD MANAGEMENT".
o --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.
o --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.
o --print-defaults
Print the current defaults and exit. This must be the first option
on the command line if it is used.
o --print-password-line
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.
Prior to MySQL 5.1.12, this option was named --passwd.
o --remove
On Windows, removes Instance Manager as a Windows service. This
assumes that Instance Manager has been run with --install
previously.
o --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.)
o --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.
o --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.
o --user=user_name
On Unix, the user name 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.)
o --username=user_name, -u user_name
Specify the user name for an entry to be added to or modified in
the password file. This option was added in MySQL 5.1.12.
o --version, -V
Display version information and exit.
o --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 5.1.7. Before that, the timeout is
30 seconds and cannot be changed.
MYSQL INSTANCE MANAGER CONFIGURATION FILES
Important
MySQL Instance Manager has been deprecated and is removed in MySQL
5.5.
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.
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 Section 5.1.2, "Server 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.
o mysqld-path = path
The path name of the mysqld server binary to use for the server
instance.
o 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.
o 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
log-bin
log-error
log=mylog
log-slow-queries
[mysqld2]
nonguarded
port=3308
server_id=2
mysqld-path= /home/cps/mysql/trees/mysql-5.1/sql/mysqld
socket = /tmp/mysql.sock5
pid-file = /tmp/hostname.pid5
datadir= /home/cps/mysql_data/data_dir1
language=/home/cps/mysql/trees/mysql-5.1/sql/share/english
log-bin
log=/tmp/fordel.log
STARTING THE MYSQL SERVER WITH MYSQL INSTANCE MANAGER
Important
MySQL Instance Manager has been deprecated and is removed in MySQL
5.5.
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/ folder.
That script invokes the mysqld_safe script by default. However, you can
use Instance Manager instead if you modify the /etc/my.cnf
configuration file by adding use-manager to the [mysql.server] section:
[mysql.server]
use-manager
Before MySQL 5.1.12, Instance Manager always tries to start at least
one server instance: When it 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 2.1.5, "Installation Layouts",
describes default locations for components of MySQL distributions.) If
you have installed the MySQL server in a nonstandard location, you
should create the Instance Manager configuration file.
The startup behavior just described is similar to that of mysqld_safe,
which always attempts to start a server. However, it lacks the
flexibility required for some operations because it is not possible to
run Instance Manager in such a way that it refrains from starting any
server instances. For example, you cannot invoke Instance Manager for
the purpose of configuring an instance without also starting it (a task
that a MySQL installer application might want to perform).
Consequently, MySQL 5.1.12 introduces the following changes:
o A new option, --mysqld-safe-compatible, may be used to cause
Instance Manager to run with startup behavior similar to that used
before MySQL 5.1.12: If Instance Manager finds a [mysqld] instance
section in the configuration file, it will start it. If Instance
Manager finds no [mysqld] section, it creates one using default
configuration values, writes a [mysqld] section to the
configuration file if it is accessible, and starts the mysqld
instance. Instance Manager also starts any other guarded instances
listed in the configuration file.
o Without --mysqld-safe-compatible, Instance Manager reads its
configuration file if it exists and starts instances for any
guarded instance sections that it finds. If there are none, it
starts no instances.
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 5.6, "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
Important
MySQL Instance Manager has been deprecated and is removed in MySQL
5.5.
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 user name 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:
o MySQL Server accounts are associated with a host name, user name,
and password (see Section 5.5.1, "User Names and Passwords").
o Instance Manager accounts are associated with a user name and
password only.
This means that a client can connect to Instance Manager with a given
user name 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
Before MySQL 5.1.12, the only option for creating password file entries
is --passwd, which causes Instance Manager to prompt for user name and
password values and display the resulting entry. You can save the
output in the /etc/mysqlmanager.passwd password file to store it. 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 user name 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
Use of the --password option fails if mysqlmanager is invoked directly
from an IBM 5250 terminal. To work around this, use a command like the
following from the command line to generate the password entry:
shell> mysql -B --skip-column-name \
-e 'SELECT CONCAT("user_name",":",PASSWORD("pass_val"));'
The output from the command can be used an entry in the
/etc/mysqlmanager.passwd file.
Beginning with MySQL 5.1.12, the --passwd option is renamed to
--print-password-line and there are several other options for managing
user accounts from the command line. For example, the --username and
--password options are available on the command line for specifying the
user name and password for an account entry. You can use them to
generate an entry with no prompting like this (type the command on a
single line):
shell> mysqlmanager --print-password-line
--username=mike --password=mikepass >> /etc/mysqlmanager.passwd
If you omit the --username or --password option, Instance Manager
prompts for the required value.
--print-password-line causes Instance Manager to send the resulting
account entry to its output, which you can append to the password file.
The following list describes other account-management options that
cause Instance Manager to operate directly on the password file. (These
options make Instance Manager scriptable for account-management
purposes.) For operations on the password file to succeed, the file
must exist and it must be accessible by Instance Manager. (The
exception is --clean-password-file, which creates the file if it does
not exist. Alternatively, if there is no password file, manually create
it as an empty file and ensure that its ownership and access modes
allow it to be read and written by Instance Manager.) The default
password file is used unless you specify a --password-file option.
To ensure consistent treatment of the password file, it should be owned
by the system account that you use for running Instance Manager to
manage server instances, and you should invoke it from that account
when you use it to manage accounts in the password file.
o Create a new user:
mysqlmanager --add-user --username=user_name [--password=password]
This command adds a new entry with the given user name and password
to the password file. The --username (or -u) option is required.
mysqlmanager prompts for the password if it is not given on the
command line with the --password (or -p) option. The command fails
if the user already exists.
o Drop an existing user:
mysqlmanager --drop-user --username=user_name
This command removes the entry with the given user name from the
password file. The user name is required. The command fails if the
user does not exist.
o Change the password for an existing user:
mysqlmanager --edit-user --username=user_name [--password=password]
This command changes the given user's password in the password
file. The user name is required. mysqlmanager prompts for the
password it is not given on the command line. The command fails if
the user does not exist.
o List existing users:
mysqlmanager --list-users
This command lists the user names of the accounts in the password
file.
o Check the password file:
mysqlmanager --check-password-file
This command performs a consistency and validity check of the
password file. The command fails if there is something wrong with
the file.
o Empty the password file:
mysqlmanager --clean-password-file
This command empties the password file, which has the effect of
dropping all users listed in it. The option creates the password
file if it does not exist, so it can be used to initialize a new
password file to be used for other account-management operations.
Take care not to use this option to reinitialize a file containing
accounts that you do not want to drop.
MYSQL SERVER INSTANCE STATUS MONITORING
Important
MySQL Instance Manager has been deprecated and is removed in MySQL
5.5.
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 5.2.3, "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.
Beginning with MySQL 5.1.12, Instance Manager tracks instance states so
that it can determine which commands are allowed for each instance. For
example, commands that modify an instance's configuration are allowed
only while the instance is offline.
Each instance is in one of the states described in the following table.
Guarded instances can be in any of the states. Nonguarded instances can
only be offline or online. Instance state information is displayed in
the status column of the SHOW INSTANCES and SHOW INSTANCE STATUS
commands.
+----------+-----------------------------+
|State | Meaning |
+----------+-----------------------------+
|offline | The instance has not been |
| | started and is not |
| | running. |
+----------+-----------------------------+
|starting | The instance is starting |
| | (initializing). Nonguarded |
| | instances cannot be |
| | in this |
| | state. A nonguarded |
| | instance goes directly |
| | from |
| | offline to |
| | online. |
+----------+-----------------------------+
|stopping | The instance is stopping. |
| | Nonguarded instances |
| | cannot be in this state. |
| | A |
| | nonguarded instance goes |
| | directly from online to |
| | offline, |
| | or stays offline if |
| | startup fails. |
+----------+-----------------------------+
|online | The instance has started |
| | and is running. |
+----------+-----------------------------+
|failed | The instance was online |
| | but it crashed and is |
| | being restarted by |
| | Instance |
| | Manager, or else the |
| | instance failed to start |
| | at all and |
| | Instance Manager is again |
| | attempting to start |
| | it. |
| | Nonguarded instances |
| | cannot be in this state. |
+----------+-----------------------------+
|crashed | Instance Manager failed to |
| | start the instance after |
| | several attempts. |
| | (Instance |
| | Manager will try again |
| | later.) Nonguarded |
| | instances |
| | cannot be in this state. |
+----------+-----------------------------+
|abandoned | Instance Manager was not |
| | able to start the |
| | instance, has given up, |
| | and |
| | will make |
| | no further attempts until |
| | instructed |
| | otherwise. |
| | To tell Instance Manager |
| | to try again, you |
| | must first |
| | use STOP INSTANCE to put |
| | the |
| | instance in offline state, |
| | and then use |
| | START |
| | INSTANCE to start the |
| | instance. |
| | If it is |
| | necessary to make |
| | configuration changes for |
| | the |
| | instance, |
| | you must do so after |
| | putting the instance |
| | offline |
| | and before starting it. |
| | (Instance Manager |
| | accepts |
| | configuration-changing |
| | commands only for offline |
| | instances.) |
| | Nonguarded instances |
| | cannot be in this |
| | state. |
+----------+-----------------------------+
CONNECTING TO MYSQL INSTANCE MANAGER
Important
MySQL Instance Manager has been deprecated and is removed in MySQL
5.5.
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
Important
MySQL Instance Manager has been deprecated and is removed in MySQL
5.5.
After you connect to MySQL Instance Manager, you can issue commands.
The following general principles apply to Instance Manager command
execution:
o Commands that take an instance name fail if the name is not a valid
instance name.
o Commands that take an instance name (other than CREATE INSTANCE)
fail if the instance does not exist.
o As of MySQL 5.1.12, commands for an instance require that the
instance be in an appropriate state. You cannot configure or start
an instance that is not offline. You cannot start an instance that
is online.
o 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.
As of MySQL 5.1.12, configuration-changing commands modify both the
in-memory cache and the server instance section recorded in the
configuration file to maintain consistency between them. For this
to occur, the instance must be offline and the configuration file
must be accessible and not malformed. If the configuration file
cannot be updated, the command fails and the cache remains
unchanged.
o 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.
o 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.
o CREATE INSTANCE instance_name [option_name[=option_value], ...]
This command configures a new instance by creating an
[instance_name] section in the configuration file. The command
fails if instance_name is not a valid instance name or the instance
already exists.
The created section instance is empty if no options are given.
Otherwise, the options are added to the section. Options should be
given in the same format used when you write options in option
files. (See Section 4.2.3.3, "Using Option Files" for a description
of the allowable syntax.) If you specify multiple options, separate
them by commas.
For example, to create an instance section named [mysqld98], you
might write something like this were you to modify the
configuration file directly:
[mysqld98]
basedir=/var/mysql98
To achieve the same effect via CREATE INSTANCE, issue this command
to Instance Manager:
mysql> CREATE INSTANCE mysqld98 basedir="/var/mysql98";
Query OK, 0 rows affected (0,00 sec)
CREATE INSTANCE creates the instance but does not start it.
If the instance name is the (deprecated) name mysqld, the option
list cannot include any options that are specific to Instance
Manager, such as nonguarded (see the section called "MYSQL INSTANCE
MANAGER CONFIGURATION FILES").
This command was added in MySQL 5.1.12.
o DROP INSTANCE instance_name
This command removes the configuration for instance_name from the
configuration file.
mysql> DROP INSTANCE mysqld98;
Query OK, 0 rows affected (0,00 sec)
The command fails if instance_name is not a valid instance name,
the instance does not exist, or is not offline.
This command was added in MySQL 5.1.12.
o 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)
o 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)
o SHOW INSTANCES
Shows the names and status of all loaded instances.
mysql> SHOW INSTANCES;
+---------------+---------+
| instance_name | status |
+---------------+---------+
| mysqld3 | offline |
| mysqld4 | online |
| mysqld2 | offline |
+---------------+---------+
o 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 |
+---------------+--------+---------+
o 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 |
+---------------+---------------------------------------------------+
o 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 |
+-------------+------------------------------------+----------+
SHOW ... LOG FILES displays information only about log files. If a
server instance uses log tables (see Section 5.2.1, "Selecting
General Query and Slow Query Log Output Destinations"), no
information about those tables is shown.
Log options are described in Section 5.1.2, "Server Command
Options".
o 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 |
+---------------------+
o 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)
As of MySQL 5.1.12, you can specify multiple options (separated by
commas), and SET can be used only for offline instances. Each
option must indicate the instance name:
mysql> SET mysqld2.port=3322, mysqld3.nonguarded;
Query OK, 0 rows affected (0.00 sec)
Before MySQL 5.1.12, only a single option can be specified. Also,
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.
o 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)
As of MySQL 5.1.12, you can specify multiple options (separated by
commas), and UNSET can be used only for offline instances. Each
option must indicate the instance name:
mysql> UNSET mysqld2.port, mysqld4.nonguarded;
Query OK, 0 rows affected (0.00 sec)
Before MySQL 5.1.12, only a single option can be specified. Also,
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.
o FLUSH INSTANCES
As of MySQL 5.1.12, FLUSH INSTANCES cannot be used unless all
instances are offline. The command causes Instance Manager to
reread the configuration file, update its in-memory configuration
cache, and start any guarded instances.
Before MySQL 5.1.12, 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)
COPYRIGHT
Copyright (C) 1997, 2010, Oracle and/or its affiliates. All rights
reserved.
This documentation is free software; you can redistribute it and/or
modify it only under the terms of the GNU General Public License as
published by the Free Software Foundation; version 2 of the License.
This documentation is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License along
with the program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA or see
http://www.gnu.org/licenses/.
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
Oracle Corporation (http://dev.mysql.com/).