howto upgrade mariadb 10.x to 10.3.x on Centos 7

#1: Perform a full backup

The first thing to do is to perform a full backup of the whole MariaDB server instance. To do so, I strongly suggest you to read this MySQL/MariaDB backup tutorial using the free mysqldump command-line tool. In very short words, here’s the one-liner:

# mysqldump -u db_root_user -p -x -A > /backup/db_backup.sql

If everything goes well, you won’t need this backup: however, since we’re performing a DB upgrade here, it’s better to be safe than sorry.

#2: Shutdown the existing MariaDB service

The next thing to do is to shutdown the existing MariaDB server. This can be done with the following command:

# sudo systemctl stop mariadb

#3: Uninstall the old MariaDB version

This step might sound scary, but don’t worry: your existing databases and your current my.cnf file won’t be deleted, only the binaries will.

# sudo yum remove mariadb mariadb-server

#4: Configure the MariaDB 10.3 repository

As soon as the previous MariaDB instance is gone, we need to install the new version: in order to do that, we need to tell our Linux machine where to find the updated binaries. If you’re using CentOS, RHEL or another yum-based distribution, you can easily do that by creating a new MariaDB10.repo file to the /etc/yum.repos.d/ folder and filling it with the following content:

# MariaDB 10.3 CentOS repository list
# http://downloads.mariadb.org/mariadb/repositories/
[mariadb]
name = MariaDB
baseurl = http://yum.mariadb.org/10.3/centos7-amd64
gpgkey=https://yum.mariadb.org/RPM-GPG-KEY-MariaDB
gpgcheck=1

In case you already have a MariaDB.repo, MariaDB10.repo or some other .repo file pointing to the old binaries, you might as well update it with the new 10.3 URIs.

#5: Install the new MariaDB 10.3 build

Now that yum will find the new binaries, we can proceed installing the new MariaDB server with the following command:

# sudo yum install mariadb mariadb-server

This will install both the client and the server.

#6: Start and Enable the new MariaDB service

Once the installation job is complete, you can restart and enable the new MariaDB server with the following commands:

# sudo systemctl start mariadb
# sudo systemctl enable mariadb

#7: Upgrade your existing database(s)

Last but not least, you need to run the mysql_upgrade command to upgrade the permission tables in the mysql database with some new fields:

# sudo mysql_upgrade

This command will also perform a very quick check of all tables and marks them as compatible with MariaDB 10.3.

Conclusion

That’s about it: I sincerely hope that this small tutorial will help you upgrading to MariaDB 10.3 and enjoy its new exciting features!