MariaDB Galera Cluster - Source Installation

MariaDB Galera Cluster is the MariaDB implementation of Galera Cluster for MySQL. Binary installation packages are available for Debian- and RPM-based distributions of Linux. If your Linux distribution is based on a different package management system, or if it runs on a different unix-like operating system where binary installation packages are not available, such as Solaris or FreeBSD, you will need to build MariaDB Galera Cluster from source.

Note

If you built MariaDB Galera Cluster over an existing standalone instance of MariaDB, there are some additional steps that you need to take in order to update your system to the new database server. For more information, see Migration.

Preparing the Server

When building from source code, make cannot manage or install dependencies for either Galera Cluster or the build process itself. You need to install these packages first.

  • For Debian-based distributions of Linux, if MariaDB is available in your repositories, you can run the following command:

    # apt-get build-dep mariadb-server
    
  • For RPM-based distributions, instead run this command:

    # yum-builddep MariaDB-server
    

In the event that neither command works for your system or that you use a different Linux distribution or FreeBSD, the following packages are required:

  • MariaDB Database Server with wsrep API: Git, CMake, GCC and GCC-C++, Automake, Autoconf, and Bison, as well as development releases of libaio and ncurses.
  • Galera Replication Plugin: SCons, as well as development releases of Boost, Check and OpenSSL.

Check with the repositories for your distribution or system for the appropriate package names to use during installation. Bear in mind that different systems may use different names and that some may require additional packages to run. For instance, to run CMake on Fedora you need both cmake and cmake-fedora.

Building MariaDB Galera Cluster

The source code for MariaDB Galera Cluster is available through GitHub. Using Git you can download the source code to build MariaDB and the Galera Replicator Plugin locally on your system.

  1. Clone the MariaDB database server repository.

    # git clone https://github.com/mariadb/server
    
  2. Checkout the branch for the version that you want to use.

    # git checkout 10.0-galera
    

    The main branches available for MariaDB Galera Cluster are:

    • 10.1
    • 10.0-galera

    Starting with version 10.1, MariaDB includes the wsrep API for Galera Cluster by default.

    Warning

    MariaDB version 10.1 is still in beta.

You now have the source files for the MariaDB database server with the wsrep API needed to function as a Galera Cluster node.

In addition to the database server, you also need the wsrep Provider, also known as the Galera Replicator Plugin. In a separate directory run the following command:

# cd ..
# git clone https://github.com/codership/galera.git

Once Git finishes downloading the source files, you can start building the database server and the Galera Replicator Plugin. You now have the source files for the database server in a server/ directory and the Galera source files in galera/.

Building the Database Server

The database server for Galera Cluster is the same as that of the standard database servers for standalone instances of MariaDB, with the addition of a patch for the wsrep API, which is packaged in the version downloaded from GitHub. You can enable the patch through the WITH_WSREP and WITH_INNODB_DISALLOW_WRITES CMake configuration options.

To build the database server, cd into the server/ directory and run the following commands:

# cmake -DWITH_WSREP=ON -DWITH_INNODB_DISALLOW_WRITES=ON ./
# make
# make install

Note

In addition to compiling through cmake and make, there are also a number of build scripts in the BUILD/ directory, which you may find more convenient to use. For example,

# ./BUILD/compile-pentium64-wsrep

This has the same effect as running the above commands with various build options pre-configured. There are several build scripts available in the directory, select the one that best suits your needs.

Building the wsrep Provider

The Galera Replication Plugin implements the wsrep API and operates as the wsrep Provider for the database server. What it provides is a certification layer to prepare write-sets and perform certification checks, a replication layer and a group communication framework.

To build the Galera Replication Plugin, cd into the galera/ directory and run SCons.

# scons

This process creates the Galera Replication Pluigin, (that is, the libgalera_smm.so file). In your my.cnf configuration file, you need to define the path to this file for the wsrep_provider parameter.

Note

For FreeBSD users, building the Galera Replication Plugin from source raises certain issues due to Linux dependencies. You can mitgate these by using the ports build available at /usr/ports/databases/galera or by installing the binary package:

# pkg install galera

Post-installation Configuration

After the build completes, there are some additional steps that you must take in order to finish installing the database server on your system. This is over and beyond the standard configuration process listed in System Configuration and Replication Configuration.

Note

Unless you defined the CMAKE_INSTALL_PREFIX configuration variable when you ran cmake above, by default the database is installed to the path /usr/local/mysql/. If you chose a custom path, adjust the commands below to accommodate the change.

  1. Create the user and group for the database server.

    # groupadd mysql
    # useradd -g mysql mysql
    
  2. Install the database.

    # cd /usr/local/mysql
    # ./scripts/mysql_install_db --user=mysql
    

    This installs the database in the working directory, (that is, at /usr/local/mysql/data). If you would like to install it elsewhere or run the script from a different directory, specify the desired paths with the --basedir and --datadir options.

  3. Change the user and group permissions for the base directory.

    # chown -R mysql /usr/local/mysql
    # chgrp -R mysql /usr/local/mysql
    
  4. Create a system unit for the database server.

    # cp /usr/local/mysql/supported-files/mysql.server \
          /etc/init.d/mysql
    # chmod +x /etc/init.d/mysql
    # chkconfig --add mysql
    

    This allows you to start Galera Cluster using the service command. It also sets the database server to start during boot.

In addition to this procedure, bear in mind that any further customization variables you enabled during the build process, such as a nonstandard base or data directory, may require you to define additional parameters in the configuration file, (that is, my.cnf).

Note

This tutorial omits MariaDB authentication options for brevity.