25 May 2023

Get upgrading from MySQL 5.7 to MySQL 8.0

An inordinate amount of our Galera Cluster customer base is still using the MySQL 5.7 variant of Galera Cluster. Besides not being able to have access to all the new features of the Galera 4 library, MySQL 5.7 is rapidly reaching End of Life (EOL) status in October 2023. This is less than six months away, and it is also why we would like to focus on getting our users upgraded to MySQL 8.0 with Galera Cluster.

Firstly, MySQL 8 has been Generally Available (GA) since 19 April 2018. That is a whole five years, and you must by now, already know that there is a new release model, where there are new features included in minor releases. The release notes are a must read. Next, Codership released Galera Cluster 4 with MySQL 8 with MySQL 8.0.19, on 25 May 2020, long after we deemed MySQL 8 stable and ready for a wide array of our customer base. Today marks our three year mark of having this software, which we have helped customers upgrade to, deploy to, and also train with. If we consider it stable enough for use, we think you really should too, because we really do care for your data. That’s for example why we skipped releasing MySQL 8.0.29, because we never want you to have an unrecoverable database.

While releasing MySQL 8 with Galera 4, we have of course dropped builds for Fedora, OpenSUSE, and even SUSE Enterprise. We have taken a focus on what our customers use the most: Red Hat Enterprise Linux (and variants like CentOS), Debian, and Ubuntu. We are cognisant of the fact that our FreeBSD users are currently left behind: the current available patches are against MySQL 5.7, and while we know the Galera 4 library runs on FreeBSD, we have not done the lifting to make the server do the same. It is entirely possible for the community to step up here.

Some reasons why you would want to upgrade if you’re on MySQL 5.7, besides all the awesome features (and strictness) of MySQL 8 are directly related to the fact that you’re moving from Galera 3 to Galera 4:

  • streaming replication
  • better foreign key support
  • group commit integrated with native MySQL 8 code
  • new system tables: wsrep_cluster, wsrep_cluster_members, wsrep_streaming_log
  • new WSREP functions
  • better handling of poor network connections, including cluster error voting protocol
  • more if you try Galera Cluster Enterprise Edition (EE), which includes XA support, GCache encryption, and the Black Box technology, in addition to a new non-blocking operations (NBO) schema upgrade option.

We have long supported in-place upgrades, we probably should note that once you go to 8.0, you’re not downgrading to 5.7. You should probably note that utf8mb4 is the new default character set. You should probably know of what has been deprecated, e.g. the query cache (which you never wanted in a Galera Cluster anyway). Note the authentication changes (caching_sha2_password is what replaces mysql_native_password), look for the obsolete data types, and new reserved words, and more.

So, in lieu of a better Galera 4, you’re also getting a better MySQL with 8.0. We are going to be covering upgrades, and why MySQL 8 a lot more in the next coming months, including with webinars, so watch this space! If you have any questions, do not forget to email us: sales@galeracluster.com.