mysqld_safe
MySQL server startup script
Synopsis
add an example, a script, a trick and tips
examples
source
mysqld_safe --skip_grant_tables &
source
How do I start mysqld with options
Your command seems fine.
You should check /var/lib/mysql/vagrant.example.com.err log file
to see why it's failing.
description
mysqld_safe
is the recommended way to start a mysqld server on
Unix. mysqld_safe adds some safety features such as
restarting the server when an error occurs and logging
runtime information to an error log file. A description of
error logging is given later in this section.
mysqld_safe
tries to start an executable named mysqld. To
override the default behavior and specify explicitly the
name of the server you want to run, specify a
--mysqld or
--mysqld-version option to
mysqld_safe. You can also use
--ledir to indicate the directory where
mysqld_safe should look for the server.
Many of the
options to mysqld_safe are the same as the options to
mysqld. See Section 5.1.3, “Server Command
Options”.
Options unknown
to mysqld_safe are passed to mysqld if they
are specified on the command line, but ignored if they are
specified in the [mysqld_safe] group of an option file. See
Section 4.2.3.3, “Using Option Files”.
mysqld_safe
reads all options from the [mysqld], [server], and
[mysqld_safe] sections in option files. For example, if you
specify a [mysqld] section like this, mysqld_safe
will find and use the --log-error
option:
[mysqld]
log-error=error.log
For backward
compatibility, mysqld_safe also reads [safe_mysqld]
sections, although you should rename such sections to
[mysqld_safe] in MySQL 5.5 installations.
mysqld_safe
supports the following options. It also reads option files
and supports the options for processing them described at
Section 4.2.3.4, “Command-Line Options that
Affect Option-File Handling”.
•
--help
Display a help
message and exit.
•
--basedir=path
The path to the
MySQL installation directory.
•
--core-file-size=size
The size of the
core file that mysqld should be able to create. The
option value is passed to ulimit -c.
•
--datadir=path
The path to the
data directory.
•
--defaults-extra-file=path
The name of an
option file to be read in addition to the usual option
files. This must be the first option on the command line if
it is used. If the file does not exist or is otherwise
inaccessible, the server will exit with an error.
•
--defaults-file=file_name
The name of an
option file to be read instead of the usual option files.
This must be the first option on the command line if it is
used.
•
--ledir=path
If
mysqld_safe cannot find the server, use this option
to indicate the path name to the directory where the server
is located.
•
--log-error=file_name
Write the error
log to the given file. See Section 5.2.2, “The
Error Log”.
•
--malloc-lib=[lib_name]
The name of the
library to use for memory allocation instead of the system
malloc() library. Any library can be used by specifying its
path name, but there is a shortcut form to enable use of the
tcmalloc library that is shipped with binary MySQL
distributions for Linux in MySQL 5.5.
The
--malloc-lib option works by
modifying the LD_PRELOAD environment value to affect dynamic
linking to enable the loader to find the
memory-allocation library when mysqld runs:
• If the
option is not given, or is given without a value
(--malloc-lib=), LD_PRELOAD is not
modified and no attempt is made to use tcmalloc.
• If the
option is given as
--malloc-lib=tcmalloc,
mysqld_safe looks for a tcmalloc library in /usr/lib
and then in the MySQL pkglibdir location (for example,
/usr/local/mysql/lib or whatever is appropriate). If tmalloc
is found, its path name is added to the beginning of the
LD_PRELOAD value for mysqld. If tcmalloc is not
found, mysqld_safe aborts with an error.
• If the
option is given as
--malloc-lib=/path/to/some/library,
that full path is added to the beginning of the LD_PRELOAD
value. If the full path points to a nonexistent or
unreadable file, mysqld_safe aborts with an
error.
• For
cases where mysqld_safe adds a path name to
LD_PRELOAD, it adds the path to the beginning of any
existing value the variable already has.
Linux users can
use the libtcmalloc_minimal.so included in binary packages
by adding these lines to the my.cnf file:
[mysqld_safe]
malloc-lib=tcmalloc
Those lines
also suffice for users on any platform who have installed a
tcmalloc package in /usr/lib. To use a specific tcmalloc
library, specify its full path name. Example:
[mysqld_safe]
malloc-lib=/opt/lib/libtcmalloc_minimal.so
•
--mysqld=prog_name
The name of the
server program (in the ledir directory) that you want to
start. This option is needed if you use the MySQL binary
distribution but have the data directory outside of the
binary distribution. If mysqld_safe cannot find the
server, use the --ledir option to
indicate the path name to the directory where the server is
located.
•
--mysqld-version=suffix
This option is
similar to the --mysqld option, but you
specify only the suffix for the server program name. The
basename is assumed to be mysqld. For example, if you
use --mysqld-version=debug,
mysqld_safe starts the mysqld-debug
program in the ledir directory. If the argument to
--mysqld-version is empty,
mysqld_safe uses mysqld in the ledir
directory.
•
--nice=priority
Use the nice
program to set the server's scheduling priority to the given
value.
•
--no-defaults
Do not read any
option files. This must be the first option on the command
line if it is used.
•
--open-files-limit=count
The number of
files that mysqld should be able to open. The option
value is passed to ulimit -n. Note that you
need to start mysqld_safe as root for this to work
properly!
•
--pid-file=file_name
The path name
of the process ID file.
•
--plugin-dir=path
The path name
of the plugin directory. This option was added in MySQL
5.5.3.
•
--port=port_num
The port number
that the server should use when listening for TCP/IP
connections. The port number must be 1024 or higher unless
the server is started by the root system user.
•
--skip-kill-mysqld
Do not try to
kill stray mysqld processes at startup. This option
works only on Linux.
•
--socket=path
The Unix socket
file that the server should use when listening for local
connections.
•
--syslog,
--skip-syslog
--syslog
causes error messages to be sent to syslog on systems that
support the logger program.
--skip-syslog suppresses the use of
syslog; messages are written to an error log file.
When syslog is
used, the daemon.err syslog priority/facility is used for
all log messages.
•
--syslog-tag=tag
For logging to
syslog, messages from mysqld_safe and mysqld
are written with a tag of mysqld_safe and mysqld,
respectively. To specify a suffix for the tag, use
--syslog-tag=tag, which
modifies the tags to be mysqld_safe-tag and
mysqld-tag.
•
--timezone=timezone
Set the TZ time
zone environment variable to the given option value. Consult
your operating system documentation for legal time zone
specification formats.
•
--user={user_name|user_id}
Run the
mysqld server as the user having the name
user_name or the numeric user ID user_id.
(“User” in this context refers to a system login
account, not a MySQL user listed in the grant tables.)
If you execute
mysqld_safe with the
--defaults-file or
--defaults-extra-file option
to name an option file, the option must be the first one
given on the command line or the option file will not be
used. For example, this command will not use the named
option file:
mysql>
mysqld_safe --port=port_num
--defaults-file=file_name
Instead, use
the following command:
mysql>
mysqld_safe
--defaults-file=file_name
--port=port_num
The
mysqld_safe script is written so that it normally can
start a server that was installed from either a source or a
binary distribution of MySQL, even though these types of
distributions typically install the server in slightly
different locations. (See Section 2.1.5,
“Installation Layouts”.) mysqld_safe
expects one of the following conditions to be true:
• The
server and databases can be found relative to the working
directory (the directory from which mysqld_safe is
invoked). For binary distributions, mysqld_safe looks
under its working directory for bin and data directories.
For source distributions, it looks for libexec and var
directories. This condition should be met if you execute
mysqld_safe from your MySQL installation directory
(for example, /usr/local/mysql for a binary
distribution).
• If the
server and databases cannot be found relative to the working
directory, mysqld_safe attempts to locate them by
absolute path names. Typical locations are
/usr/local/libexec and /usr/local/var. The actual locations
are determined from the values configured into the
distribution at the time it was built. They should be
correct if MySQL is installed in the location specified at
configuration time.
Because
mysqld_safe tries to find the server and databases
relative to its own working directory, you can install a
binary distribution of MySQL anywhere, as long as you run
mysqld_safe from the MySQL installation
directory:
shell>
cd mysql_installation_directory
shell> bin/mysqld_safe &
If
mysqld_safe fails, even when invoked from the MySQL
installation directory, you can specify the
--ledir and --datadir
options to indicate the directories in which the server and
databases are located on your system.
Beginning with
MySQL 5.5.21, mysqld_safe tries to use the
sleep and date system utilities to determine
how many times it has attempted to start this second,
and—if these are present and this is greater than 5
times—is forced to wait 1 full second before starting
again. This is intended to prevent excessive CPU usage in
the event of repeated failures. (Bug #11761530, Bug
#54035)
When you use
mysqld_safe to start mysqld,
mysqld_safe arranges for error (and notice) messages
from itself and from mysqld to go to the same
destination.
There are
several mysqld_safe options for controlling the
destination of these messages:
•
--syslog: Write error messages to syslog
on systems that support the logger program.
•
--skip-syslog: Do not write error
messages to syslog. Messages are written to the default
error log file (host_name.err in the data directory),
or to a named file if the
--log-error option is given.
•
--log-error=file_name: Write
error messages to the named error file.
If none of
these options is given, the default is
--skip-syslog.
If
--syslog and
--log-error are both given, a
warning is issued and --log-error
takes precedence.
When
mysqld_safe writes a message, notices go to the
logging destination (syslog or the error log file) and
stdout. Errors go to the logging destination and stderr.
Normally, you
should not edit the mysqld_safe script. Instead,
configure mysqld_safe by using command-line
options or options in the [mysqld_safe] section of a my.cnf
option file. In rare cases, it might be necessary to edit
mysqld_safe to get it to start the server properly.
However, if you do this, your modified version of
mysqld_safe might be overwritten if you upgrade MySQL
in the future, so you should make a copy of your edited
version that you can reinstall.
copyright
Copyright © 1997, 2013, Oracle and/or its affiliates. All rights
reserved.
This software and related documentation are provided under a
license agreement containing restrictions on use and disclosure
and are protected by intellectual property laws. Except as
expressly permitted in your license agreement or allowed by law,
you may not use, copy, reproduce, translate, broadcast, modify,
license, transmit, distribute, exhibit, perform, publish, or
display any part, in any form, or by any means. Reverse
engineering, disassembly, or decompilation of this software,
unless required by law for interoperability, is prohibited.
The information contained herein is subject to change without
notice and is not warranted to be error-free. If you find any
errors, please report them to us in writing.
If this software or related documentation is delivered to the
U.S. Government or anyone licensing it on behalf of the U.S.
Government, the following notice is applicable:
U.S. GOVERNMENT RIGHTS Programs, software, databases, and related
documentation and technical data delivered to U.S. Government
customers are "commercial computer software" or "commercial
technical data" pursuant to the applicable Federal Acquisition
Regulation and agency-specific supplemental regulations. As such,
the use, duplication, disclosure, modification, and adaptation
shall be subject to the restrictions and license terms set forth
in the applicable Government contract, and, to the extent
applicable by the terms of the Government contract, the
additional rights set forth in FAR 52.227-19, Commercial Computer
Software License (December 2007). Oracle USA, Inc., 500 Oracle
Parkway, Redwood City, CA 94065.
This software is developed for general use in a variety of
information management applications. It is not developed or
intended for use in any inherently dangerous applications,
including applications which may create a risk of personal
injury. If you use this software in dangerous applications, then
you shall be responsible to take all appropriate fail-safe,
backup, redundancy, and other measures to ensure the safe use of
this software. Oracle Corporation and its affiliates disclaim any
liability for any damages caused by use of this software in
dangerous applications.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. MySQL is a trademark of Oracle Corporation and/or its
affiliates, and shall not be used without Oracle’s express
written authorization. Other names may be trademarks of their
respective owners.
This software and documentation may provide access to or
information on content, products, and services from third
parties. Oracle Corporation and its affiliates are not
responsible for and expressly disclaim all warranties of any kind
with respect to third-party content, products, and services.
Oracle Corporation and its affiliates will not be responsible for
any loss, costs, or damages incurred due to your access to or use
of third-party content, products, or services.
This document in any form, software or printed matter, contains
proprietary information that is the exclusive property of Oracle.
Your access to and use of this material is subject to the terms
and conditions of your Oracle Software License and Service
Agreement, which has been executed and with which you agree to
comply. This document and information contained herein may not be
disclosed, copied, reproduced, or distributed to anyone outside
Oracle without prior written consent of Oracle or as specifically
provided below. This document is not part of your license
agreement nor can it be incorporated into any contractual
agreement with Oracle or its subsidiaries or affiliates.
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 Oracle disseminates it (that is,
electronically for download on a Web site with the software) or
on a CD-ROM or similar medium, provided however that the
documentation is disseminated together with the software on the
same medium. Any other use, such as any dissemination of printed
copies or use of this documentation, in whole or in part, in
another publication, requires the prior written consent from an
authorized representative of Oracle. Oracle and/or its affiliates
reserve any and all rights to this documentation not expressly
granted above.
For more information on the terms of this license, or for details
on how the MySQL documentation is built and produced, please
visit MySQL Contact &
Questions.
For additional licensing information,
including licenses for third-party libraries used by MySQL
products, see Preface and Legal Notices.
For help with using MySQL, please visit
either the MySQL
Forums or MySQL Mailing Lists where you can discuss your issues with other MySQL
users.
For additional documentation on MySQL
products, including translations of the documentation into other
languages, and downloadable versions in variety of formats,
including HTML and PDF formats, see the MySQL Documentation Library.
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/).