Skip navigation links
MySQL 3.23, 4.0, 4.1 Reference Manual :: 4 MySQL Programs :: 4.4 MySQL Installation-Related Programs :: 4.4.6 mysql_install_db — Initialize MySQL Data Directory
4.4.7 mysql_secure_installation — Improve MySQL Installation Security »
Section Navigation      [Toggle]

4.4.6. mysql_install_db — Initialize MySQL Data Directory

mysql_install_db initializes the MySQL data directory and creates the system tables that it contains, if they do not exist.

To invoke mysql_install_db, use the following syntax: 

shell> mysql_install_db [options]

Because the MySQL server, mysqld, needs to access the data directory when it runs later, you should either run mysql_install_db from the same account that will be used for running mysqld or run it as root and use the --user option to indicate the user name that mysqld will run as. It might be necessary to specify other options such as --basedir or --datadir if mysql_install_db does not use the correct locations for the installation directory or data directory. For example: 

shell> bin/mysql_install_db --user=mysql \
         --basedir=/opt/mysql/mysql \
         --datadir=/opt/mysql/mysql/data

mysql_install_db supports the following options, which can be specified on the command line or in the [mysql_install_db] and (if they are common to mysqld) [mysqld] option file groups.

  • --basedir=path

    The path to the MySQL installation directory.

  • --force

    Cause mysql_install_db to run even if DNS does not work. In that case, grant table entries that normally use host names will use IP addresses.

  • --datadir=path, --ldata=path

    The path to the MySQL data directory.

  • --rpm

    For internal use. This option is used by RPM files during the MySQL installation process.

  • --skip-name-resolve

    Use IP addresses rather than host names when creating grant table entries. This option can be useful if your DNS does not work.

  • --user=user_name

    The login user name to use for running mysqld. Files and directories created by mysqld will be owned by this user. You must be root to use this option. By default, mysqld runs using your current login name and files and directories that it creates will be owned by you.

  • --verbose

    Verbose mode. Print more information about what the program does.

  • --windows

    For internal use. This option is used for creating Windows distributions.


User Comments

Posted by Tarun Dua on May 21 2004 4:00pm[Delete] [Edit]

While instalingl mysql-4.0.20 from source on a Redhat 9 box which had mysql-3.23.xx preinstalled. I also needed to move the /etc/my.cnf to another location while I installed the privilege tables using bin/msyql_install_db

Posted by camden lindsay on January 5 2006 5:54pm[Delete] [Edit]

For all the linux Newbies out there--
I ran into an error 13- not allowing access to the /root/tmp folder. This essentially what is listed earlier on the page as you do not have write access to /tmp.

In my case this was due to the TMPDIR environtmental variable being set to /root/tmp. To view the environtmental variables, type 'env'.

By running the commands suggested, you temporarily change the TMPDIR environmental variable to /some_tmp_dir. If you have defined your MYSQL_UNIX_PORT in your build, it should probably be that directory.

shell> TMPDIR=/some_tmp_dir/
shell> MYSQL_UNIX_PORT=/some_tmp_dir/mysql.sock
shell> export TMPDIR MYSQL_UNIX_PORT

hope this helps someone

Posted by Jack Daniels on July 28 2006 11:10pm[Delete] [Edit]

If you suspect permission problems and but find all file and
directory permissions in place and ok then selinux must be
giving the problem. I know because I ran into it.

Try disabling selinux (by running system-config-securitylevel
on fedora core 3 which i have) and retry. It things work out
then fine tune selinux for your system

Posted by Rick Pelleg on December 23 2006 6:08am[Delete] [Edit]

After installing the distribution package mysql-standard-5.0.27-solaris8-sparc-64bit.pkg in its default location (/opt/mysql/mysql) I had to explicitely set the datadir when running "mysql_install_db":

mysql_install_db --user=mysql --datadir=/opt/mysql/mysql/data

otherwise, mysqld_safe failed with "Fatal error: Can't open and lock privilege tables: Table 'mysql.host' doesn't exist". I found the error by specifying --log-error:

mysqld_safe --user=mysql --verbose --log-error=/tmp/mysql.error.log



Posted by Don Cohen on September 11 2007 11:23pm[Delete] [Edit]

mysql_install_db by default reads /etc/my.cnf
If you want it to read configuration data from somewhere else:
bin/mysql_install_db -defaults-file=somewhere-else

Posted by Ed Lazor on December 2 2009 4:59am[Delete] [Edit]

Ubuntu 9.10
Moving the database from /var/lib/mysql to /data/databases/mysql

You'll get errors when running mysql_install_db until you go into /etc/apparmor.d, update the usr.sbin.mysql file, and run /etc/init.d/apparmor restart

You may also get an error when running /etc/init.d/mysql start:

Access denied for user debian-sys-maint at localhost

Check /etc/mysql/debian.cnf for the account information.

You'll need to run mysql, add the grant tables, and then restart mysql.

Add your own comment.