Switching Between Different Installed MariaDB Versions

This article is about managing many different installed MariaDB versions and running them one at a time. This is useful when doing benchmarking, testing, or for when developing different MariaDB versions.

This is most easily done using the tar files from downloads.askmonty.org.

Stopping a pre-installed MySQL/MariaDB from interfering with your tests

If MySQL/MariaDB is already installed and running, you have two options:

1. Use test MariaDB servers with a different port & socket.
   • In this case you are probably best off creating a specific section for MariaDB in your ~/.my.cnf file.
2. Stop mysqld with /etc/rc.d/mysql stop or mysqladmin shutdown.

Note that you don't have to uninstall or otherwise remove MySQL!

How to create a binary distribution (tar file)

Here is a short description of how to generate a tar file from a source distribution. If you have downloaded a binary tar file, you can skip this section.

The steps to create a binary tar file are:

• Decide where to put the source. A good place is under /usr/local/src/mariadb-5.#.
• Get the source
• Compile the source
• Create the binary tar ball.

You will then be left with a tar file named something like: mariadb-5.3.2-MariaDB-beta-linux-x86_64.tar.gz

Creating a directory structure for the different installations

Install the binary tar files under /usr/local/ with the following directory names (one for each MariaDB version you want to use):

• mariadb-5.1
• mariadb-5.2
• mariadb-5.3
• mariadb-5.5
• mariadb-10.0

The above assumes you are just testing major versions of MariaDB. If you are testing specific versions, use directory names like mariadb-5.3.2

With the directories in place, create a sym-link named mariadb which points at the mariadb-XXX directory you are currently testing. When you want to switch to testing a different version, just update the sym-link.

Example:

cd /usr/local
tar xfz /tmp/mariadb-5.3.2-MariaDB-beta-linux-x86_64.tar.gz
mv -vi mariadb-5.3.2-MariaDB-beta-linux-x86_64 mariadb-5.3
ln -vs mariadb-5.3 mariadb

Setting up the data directory

When setting up the data directory, you have the option of either using a shared database directory or creating a unique database directory for each server version. For testing, a common directory is probably easiest. Note that you can only have one mysqld server running against one data directory.

Setting up a common data directory

The steps are:

1. Create the mysql system user if you don't have it already! (On Linux you do it with the useradd command).
2. Create the directory (we call it mariadb-data in the example below) or add a symlink to a directory which is in some other place.
3. Create the mysql permission tables with mysql_install_db

cd /usr/local/
mkdir mariadb-data
cd mariadb
./bin/mysql_install_db --no-defaults --datadir=/usr/local/mariadb-data
chown -R mysql mariadb-data mariadb-data/*

The reason to use --no-defaults is to ensure that we don't inherit incorrect options from some old my.cnf.

Setting up different data directories

To create a different data directories for each installation:

cd mariadb
./scripts/mysql_install_db --no-defaults
chown -R mysql mariadb-data mariadb-data/*

This will create a directory data inside the current directory.

If you want to use another disk you should do:

cd mariadb
ln -s path-to-empty-directory-for-data data
./scripts/mysql_install_db --no-defaults --datadir=./data
chown -R mysql mariadb-data mariadb-data/*

Running a MariaDB server

The normal steps are:

rm mariadb
ln -s mariadb-5.# mariadb
cd mariadb
./bin/mysqld_safe --no-defaults --datadir=/usr/local/mariadb-data &

Setting up a .my.cnf file for running multiple MariaDB main versions

If you are going to start/stop MariaDB a lot of times, you should create a ~/.my.cnf file for the common options you are using.

The following example shows how to use a non-standard TCP-port and socket (to not interfere with a main MySQL/MariaDB server) and how to setup different options for each main server:

[client-server]
socket=/tmp/mysql.sock
port=3306
[mysqld]
datadir=/usr/local/mariadb-data

[mariadb-5.2]
# Options for MariaDB 5.2
[mariadb-5.3]
# Options for MariaDB 5.3

If you create an ~/.my.cnf file, you should start mysqld with --defaults-file=~/.my.cnf instead of --no-defaults in the examples above.