There are three different ways ProxySQL can direct traffic between your application and the backend MySQL services.

1. Locally, on the MySQL servers.
2. Between the MySQL servers and the application.
3. Colocated on the application servers themselves.

Without going through too much detail – each has its own limitations. In the first form, the application needs to know about all MySQL servers at any given point in time. With the third form, a large number of application servers, especially in the age of Kubernetes, where apps can simply recycle easily or be scaled up and down, backend connections can increase exponentially leading to issues.

In the second form, load balancing between a pool of ProxySQL servers is normally the challenge. Do you load balance the load balancers? While there are approaches like balancing from the application, similar to how the MongoDB drivers works, the …

Percona announces the release of Percona XtraDB Cluster Operator 0.3.0 early access.

The Percona XtraDB Cluster Operator simplifies the deployment and management of Percona XtraDB Cluster in a Kubernetes or OpenShift environment. It extends the Kubernetes API with a new custom resource for deploying, configuring and managing the application through the whole life cycle.

You can install the Percona XtraDB Cluster Operator on Kubernetes or OpenShift. While the operator does not support all the Percona XtraDB Cluster features in this early access release, instructions on how to install and configure it …

Distributed systems are hard – I just want to echo that. In MySQL, we have quite a number of options to run highly available systems. However, real fault tolerant systems are difficult to achieve.

Take for example a common use case of multi-DC replication where Orchestrator is responsible for managing the topology, while ProxySQL takes care of the routing/proxying to the correct server, as illustrated below. A rare case you might encounter is that the primary MySQL

node01

on DC1 might have a blip of a couple of seconds. Because Orchestrator uses an adaptive health check – not only the node itself but also consults its replicas – it can react really fast and promote the node in DC2.

Why is this problematic?

The problem occurs when

node01

resolves its temporary issue. A race condition could occur within ProxySQL that could mark it back as read-write. You can increase an …

If you are using Galera replication, you know that schema changes may be a serious problem. With its current implementation, there is no way even a simple ALTER will be unobtrusive for live production traffic. It is a fact that with the default TOI alter method, Percona XtraDB Cluster (PXC) cluster suspends writes in order to execute the ALTER in the same order on all nodes.

For factual data structure changes, we have to adapt to the limitations, and either plan for a maintenance window, or use pt-online-schema-change, where interruptions should be very short. I suggest you be extra careful here, as normally you …

Join Percona CEO Peter Zaitsev as he presents High Availability and Disaster Recovery in Amazon RDS on Wednesday, March 6th, 2019, at 11:00 AM PST (UTC-8) / 2:00 PM EST (UTC-5).

Register Now

In this hour-long webinar, Peter describes the differences between high availability (HA) and disaster recovery (DR). Afterward, Peter will go through scenarios detailing how each is handled manually and in Amazon RDS.

He will review the pros and cons of managing HA and DR in the traditional …

Percona is glad to announce the release of Percona XtraDB Cluster 5.6.43-28.32 on February 28, 2019. Binaries are available from the downloads section or from our software repositories.

This release of Percona XtraDB Cluster includes the support of Ubuntu 18.10 (Cosmic Cuttlefish). Percona XtraDB Cluster 5.6.43-28.32 is now the current release, based on the following:

• Percona Server 5.6.43-84.3
• Codership WSREP API release 5.6.42
• Codership Galera library 3.25

All Percona software is …

Percona is glad to announce the release of Percona XtraDB Cluster 5.7.25-31.35 on February 28, 2018. Binaries are available from the downloads section or from our software repositories.

This release of Percona XtraDB Cluster includes the support of Ubuntu 18.10 (Cosmic Cuttlefish). Percona XtraDB Cluster 5.7.25-31.35 is now the current release, based on the following:

• Percona Server for MySQL 5.7.25-28
• Galera Replication library 3.25
• Galera/Codership WSREP API Release 5.7.24

All Percona software is open-source and free.

Bugs Fixed

…

Percona announces the release of Percona XtraDB Cluster Operator  0.2.0 early access.

The Percona XtraDB Cluster Operator simplifies the deployment and management of Percona XtraDB Cluster in a Kubernetes or OpenShift environment. It extends the Kubernetes API with a new custom resource for deploying, configuring and managing the application through the whole life cycle.

Note: PerconaLabs and Percona-QA are open source GitHub repositories for unofficial scripts and tools created by Percona staff. These handy utilities can help save your time and effort.

Percona software builds located in the Percona-Lab and Percona-QA repositories are not officially …

It’s a few weeks after AWS re:Invent 2018 and my head is still spinning from all of the information released at this year’s conference. This year I was able to enjoy a few sessions focused on Aurora deep dives. In fact, I walked away from the conference realizing that my own understanding of High Availability (HA), Disaster Recovery (DR), and Durability in Aurora had been off for quite a while. Consequently, I decided to put this blog out there, both to collect the ideas in one place for myself, and to share them in general. Unlike some of our previous blogs, I’m not focused on analyzing Aurora performance or examining the architecture behind Aurora. Instead, I want to focus on how HA, DR, and Durability are defined and implemented within the Aurora ecosystem.  We’ll get just deep enough into the weeds to be able to examine these capabilities alone.

Aurora MySQL – What is it?

We’ll start with a simplified …

Percona announces the release of Percona XtraDB Cluster 5.6.42-28.30 (PXC) on January 4, 2019. Binaries are available from the downloads section or our software repositories.

Percona XtraDB Cluster 5.6.42-28.30 is now the current release, based on the following:

• Percona Server 5.6.42
• Codership WSREP API release 5.6.42
• Codership Galera library 3.25

All Percona software is open-source and free.

Fixed …