So MySQL's group replication came out with MySQL 5.7. Now that is has been out a little while people are starting to ask more about it.

• https://dev.mysql.com/doc/refman/8.0/en/group-replication.html
• https://dev.mysql.com/doc/refman/8.0/en/group-replication-deploying-in-single-primary-mode.html

Below is an example of how to set this up and a few pain point examples as I poked around with it.
I am using three different servers,

 Server CENTOSA

mysql> INSTALL PLUGIN group_replication SONAME 'group_replication.so';
Query OK, 0 rows affected (0.02 sec)

vi my.cnf
…

With the release of version 8.0.16 of MySQL, we’ve added some features to the Group Replication (GR) plugin, in order to enhance its high-availability capacities. One of these features was the ability to enable a member that has left the group, under certain circumstances, to automatically rejoin it, without need of intervention by the user.…

Q: Validate an instance for MySQL InnoDB Cluster usage?

A: Use check_instance_configuration()

To operate more easily a MySQL Group Replication (InnoDB Cluster), the Group Replication plugins provides some UDFs.

If you have read the recent article from Tiago Vale about the Group Replication Communication Protocol, you may have heard about two new UDFs allowing to get or set  the communication protocol.

So what are all the UDFs provided with the Group Replication and what’s their purpose ?

SELECT UDF_NAME FROM performance_schema.user_defined_functions 
WHERE UDF_NAME LIKE 'group_repl%';
+-------------------------------------------------+
 | UDF_NAME                                        |
 +-------------------------------------------------+
 | group_replication_get_communication_protocol    |
 | group_replication_get_write_concurrency         |
 | group_replication_set_as_primary                | …

In a previous blog post we presented the message fragmentation functionality that you can use starting with MySQL Group Replication 8.0.16.

No group member can have a version < 8.0.16 if you wish to use message fragmentation in a group. MySQL 8.0.16 also ships with a new Group Replication concept to help you ensuring backwards compatibility: the group’s communication protocol.…

MySQL 8.0.16 is out and it enhances Group Replication as usual. For example, the group_replication_exit_state_action system variable has a new default value, and members that the group expels can now automatically try to rejoin. This post presents a new feature MySQL 8.0.16 brings to Group Replication: message fragmentation.…

At the end of the month, some engineers of the MySQL Team will be present in Austin, TX !

We will attend the first edition of Percona Live USA in Texas.

During that show, you will have the chance to meet key engineers, product managers, as well as Dave and myself.

Let me present you the Team that will be present during the conference:

The week will start with the MySQL InnoDB Cluster full day tutorial by Kenny and myself. This tutorial is a full hands-on tutorial where we will start by migrating a classical asynchronous master-replicas topology to a new MySQL InnoDB Cluster. We will then experience …

As explained in this previous post, it’s now (since 8.0.16) possible to use the MySQL Shell Reporting Framework to monitor MySQL InnoDB Cluster.

Additionally, when a member of the MySQL InnoDB Cluster’s Group leaves the group for any reason, or when a new node is added from a backup, this member needs to sync up with the other nodes of the cluster. This process is called the Distributed Recovery.

During the Distributed Recovery, the joiner receives from a donor all the missing transactions using asynchronous replication on a dedicated channel.

It’s of course also possible to monitor the progress of this recovery process by calculating how many transactions have …

With MySQL Shell 8.0.16, a new very interesting feature was released: the Reporting Framework.

Jesper already blogged about it and I recommend you to read his articles if you are interested in writing your own report:

• https://mysql.wisborg.dk/2019/04/26/mysql-shell-8-0-16-built-in-reports/
• https://mysql.wisborg.dk/2019/04/27/mysql-shell-8-0-16-user-defined-reports/

I this post, I will show you one user-defined report that can be used to monitor your MySQL InnoDB Cluster / Group Replication.

Preparation

Before being able to use the report, you need to download 2 files. The first one is the …

MySQL 8.0.16 has been released last Thursday. In it, you can find some new replication features. Here is a quick summary. Follow-up blog posts will provide details about these features.

• Large Messages Fragmentation Layer for Group Replication. Tiago Vale’s work, introduces message fragmentation to the Group Communication Framework.

…