When you connect to a server (or cluster) using a TCP proxy level 7, also referred to as an application-level or Layer 7 proxy (highest level of the OSI model), the application doesn’t connect directly to the back-end server(s). The proxy usually understands the protocol used and can eventually take some decisions or even change the request.

The problem when using such proxy (like HA Proxy, ProxySQL and MySQL Router) is that the server doesn’t really know from where the client is connecting. The server sees the IP address of the proxy/router as the source IP of the client.

HA Proxy initially designed the Proxy Protocol, a simple protocol that allows a TCP connection to transport proxy-related information between the client, the proxy server and the destination server. The main purpose of the Proxy Protocol is then to preserve the client’s original IP address (with some others metadata). See …

MySQL InnoDB Cluster is the official High Availability solution for and from MySQL.

MySQL InnoDB Cluster is composed by MySQL Server, MySQL Group Replication, MySQL Router and MySQL Shell.

Before InnoDB Cluster there was no standard solution for MySQL Availability and many custom solutions were used (some better than the others). But there was a good solution using some similar principles of MySQL Group Replication: Galera.

Now that MySQL InnoDB Cluster is mature and easier to orchestrate than galera, I receive a lot of requests on how to migrate from Galera (or Percona XtraDB Cluster) to MySQL InnoDB Cluster.

I already wrote some time ago an article on this process: how to migrate from Galera to MySQL Group Replication.

In this article we will see how we can migrate from Percona XtraDB …

MySQL InnoDB Cluster is the High Availability solution for MySQL. It delivers automatic fail-over and guarantees zero data loss (RPO=0).

RPO: Recovery Point Objective describes the interval of time that might pass during a disruption before the quantity of data lost during that period exceeds the Business Continuity Plan’s maximum allowable tolerance.

Example: our business architecture needs to have RPO=2 minutes. This means that in case of failure, 2 minutes of data can be lost.

However, and we saw this recently in Europe, an entire data center can “disappear” instantaneously… So it’s also important to have a Disaster Recovery plan.

One solution, is to have an InnoDB Cluster (Group Replication) that spans across multiple regions. However, this is often not feasible because of high latency across regions.

Another solution is InnoDB Cluster in one region with Asynchronous …

I wanted to be brave and I installed MySQL Group Replication manually…. it was painful !

Then I realized that managing those servers and especially deal with MySQL Routers was even more painful !

What are my options now ? Is there a solution or do I need to restart from scratch ?

Asking the answer is already answering it… and once again MySQL Shell at the rescue.

MySQL Group Replication

I’ve configured everything manually. I also loaded group_replication and clone plugins and finally after having bootstrapped my Group here is what I have:

mysql> select member_host, member_port port, member_state state, 
       member_role role, member_version version 
       from performance_schema.replication_group_members;
+-------------+------+--------+-----------+---------+
| member_host | port | state  | role      | version | …

A few days ago, a customer got in touch asking how they could use Percona Monitoring and Management (PMM) to monitor the roles played by each node in an InnoDB cluster. More specifically, they wanted to check when one of the nodes changed its role from Primary to Secondary, or vice-versa. PMM allows for a high level of flexibility and customization through its support for custom queries, and we just have to be creative on how we approach the problem. In this post, we present the steps we did to test our solution, including the deployment of a 3-node InnoDB Cluster hosted in the same server (for testing) and a PMM 2 server, and connecting them together. Even though this has already been covered in other blog …

Just recently, I have been asked to look into what a Disaster Recovery site for InnoDB Cluster would look like.

If you’re reading this, then I assume you’re familiar with what MySQL InnoDB Cluster is, and how it is configured, components, etc.

Reminder: InnoDB Cluster (Group Replication, Shell & Router) in version 8.0 has had serious improvements from 5.7. Please try it out.

So, given that, and given that we want to consider how best to fulfill the need, i.e. create a DR site for our InnoDB Cluster, let’s get started.

Basically I’ll be looking at the following scenario:

InnoDB Cluster Source site with a Group Replication Disaster Recovery Site.

Now, just before we get into the nitty-gritty, here’s the scope.

Life is already hard enough, so we want as much automated as possible, so, yes, InnoDB Cluster gets some of that done, but there are other parts we will still have …

In this demo we are setting up InnDB Cluster on Kubernetes, we will use a StatefulSets and NFS as storage. This demo was created on Oracle Cloud (OCI) but vanilla Kubernetes and NFS was used so should work for any cloud or on-prem. More information on my github page here Setup NFS Server to act as your persistent volume. Setup a NFS Server for your persistent volumes, howto here If you are using a public cloud provider you can most likely use dynamic storage options for handling of PV. In bellow examples I have a NFS Server on IP: 10.0.0.50 This NFS exposes folders: …

With this post we are reaching the end of our journey to HA for WordPress & MySQL 8.0 on OCI.

If you have not read the two previous articles, this is just the right time.

• MySQL 8.0 InnoDB ReplicaSet with WordPress in OCI
• MySQL 8.0 InnoDB ReplicaSet with WordPress in OCI – part II

We started this trip using the MySQL InnoDB ReplicaSet where only 2 servers are sufficient but doesn’t provide automatic fail-over.

In this article we will upgrade our InnoDB ReplicaSet to …

In the previous post, we setup a Drupal website with MySQL as backend on a different compute instance in a different subnet.

Today we will increase the High Availability of our Database by transforming this single MySQL instance into a MySQL InnoDB Cluster!

The architecture will be the following:

We will use 2 different Availability Domains (AD), of course we could have used 3, it’s up to you.

We will install MySQL Router on the Application Server as advised, and we will modify our Drupal’s configuration to connect locally on the R/W port of the MySQL Router.

You will see that this is very easy to achieve, the most …

As you know, Oracle Cloud Infrastructure (aka OCI) becomes more and more popular. You can find OCI data centers almost everywhere and the price is very attractive.

Something very interesting is the possibility to have different availability domains but also different fault-domains in the same availability one !

Oracle provides a lot of modules to deploy your architecture on OCI using Terraform. Those are called oracle-quickstart repos. You can find them on Github.

There is an official Reference Architecture for MySQL InnoDB Cluster in OCI that I encourage you to read before deploying your MySQL HA solution …