As you may know by now, MySQL 8.0.2 DMR is out ! \o/

Many features have been added (see Geir Høydalsvik‘s announcement) and of course the replication also brought new features and improvements (see this post from Luís Soares).

But some improvements in the monitoring broke the added sys view used by ProxySQL to monitor the state of a member of the group:

mysql> select * from sys.gr_member_routing_candidate_status;
+------------------+-----------+---------------------+----------------------+
| viable_candidate | read_only | transactions_behind | transactions_to_cert | …

MySQL InnoDB Cluster (or only Group Replication) becomes more and more popular. This solution doesn’t attract only experts anymore. On social medias, forums and other discussions, people are asking me what it the best way to migrate a running environment using traditional asynchronous replication [Master -> Slave(s)] to InnoDB Cluster.

The following procedure is what I’m actually recommending. These steps have for objective to reduce the downtime to the minimum for the database service.

We can divide the procedure in 9 steps:

1. the current situation
2. preparing the future cluster
3. data transfert
4. replication from current system
5. creation of the cluster with a single instance
6. adding instances to the cluster
7. configure the router
8. test phase
9. pointing the application to the new solution

…

A few weeks ago I started experimenting with MySQL InnoDB cluster. As part of the testing, I tried to kill a node to see what happens to the cluster.

The good news is that the cluster is resilient. When the primary node goes missing, the cluster replaces it immediately, and operations continue. This is one of the features of an High Availability system, but this feature alone does not define the usefulness or the robustness of the system. In one of my previous jobs, I worked at testing a commercial HA system and I've learned a few things about what makes a reliable system.

Armed with this knowledge, I did some more experiments with InnoDB Cluster. The attempt from my previous article had no other expectation than seeing operations continue with ease (primary node …

Today I presented MySQL InnoDB Cluster at the Helsinki MySQL User Group.

To demonstrate how easy it’s to deploy a cluster with MySQL Shell and used the prompt that will be part of a future release just because it’s beautiful.

If you also want to see how it looks like, just check the video below:

There were several MongoDB users in the audience and I got only very positive feedback, they were very surprised how easy it’s to deploy a MySQL InnoDB Cluster these days !

InnoDB Cluster was released as GA a few weeks ago. I remember the initial announcement of the product at OOW 2016, promising a seamless solution for replication and high availability with great ease of use. I was a bit disappointed to see that, at GA release time, the InnoDB Cluster is a patchwork of three separate products (Group Replication, MySQL Router, MySQL Shell) which the users have to collect and install separately.

Given this situation, I was very pleased when Matthew Lord published Docker-InnoDB-Cluster, an image for Docker that contains everything you need to get the system up and running. The …

ProxySQL is the leader in proxy and load balancing solution for MySQL. It has great features like query caching, multiplexing, mirroring, read/write splitting, routing, etc… The latest enhancement in ProxySQL is the native support of MySQL Group Replication. No more need to use an external script within the scheduler like I explained in this previous post.

This implementation supports Groups in Single-Primary and in Multi-Primary mode. It is even possible to setup a Multi-Primary Group but dedicate writes on only one member.

René, the main developer of ProxySQL, went even further. For example in a 7 nodes clusters (Group …

Yesterday I was invited to speak at the “Jeudis du Libre” in Mons.

The location was very special as it was in one auditorium of Polytech, the oldest university in the city of Mons.

I presented in French two very hot topics in the MySQL ecosystem:

• MySQL InnoDB Cluster
• MySQL as Document Store with JSON datatype & X plugin

Those are very new technologies illustrating MySQL’s innovation. And of course there is much more to come with MySQL 8 !

Here are the slides if you are interested:

Jeudis du Libre – MySQL InnoDB Cluster from Frederic Descamps

…

We saw yesterday that the new MySQL Shell was out and how we could create a MySQL InnoDB Cluster manually using the Shell.

Today, I would like to show you how easy it is to create recipes to automate all the process. I have created a Puppet module that can be used as Proof-of-concept (You might need more features to use it in production, feel free to fork it).

The module can be found on this github repo.

When using Puppet, I really like to put all configuration in hiera.

Environment

We have 3 GNU/Linux servers: mysql1, mysql2 and mysql3.

We won’t install anything related to MySQL manually, everything will be handled by Puppet.

Nodes definition …

 Earlier this week,  MySQL Shell 1.08 has been released. This is the first Release Candidate of this major piece of MySQL InnoDB Cluster.

Some commands have been changed and some new ones were added.

For example the following useful commands were added:

• dba.checkInstanceConfiguration()
• cluster.checkInstanceState()
• dba.rebootClusterFromCompleteOutage()

So let’s have a look on how to use the new MySQL Shell to create a MySQL InnoDB Cluster.

Action Plan

We have 3 blank Linux servers: mysql1, mysql2 and mysql3 all running rpm based Linux version 7 (Oracle Linux 7, CentOS 7, …).

We will install the required MySQL yum repositories and install the needed packages …

The slides of my joint tutorial with Kenny Gryp from Percona on MySQL InnoDB Cluster and Group Replication are now online.

We got nice questions during the session and very good feedback.

MySQL Group Replicatio in a nutshell – MySQL InnoDB Cluster from Frédéric Descamps