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How ProxySQL adds Failover and Query Control to your MySQL Replication Setup

An overview of ProxySQL in a MySQL replication environment, and how ProxySQL adds features like failover and query control to the setup.

ClusterControl Developer Studio: automatically scale your clusters

This post describes how to automatically scale a MySQL Replication topology via advisors, written in the ClusterControl Developer Studio.

MySQL Load Balancing with ProxySQL - an Overview

An overview of ProxySQL, an SQL-aware load balancer for MySQL and MariaDB. This blog post explains the concepts behind ProxySQL, and goes through installation and configuration.

Newly Updated “MySQL Load Balancing with HAProxy” Tutorial

We have recently updated our tutorial on MySQL Load Balancing with HAProxy.  Read about deployment and configuration, monitoring, ongoing maintenance, health check methods, read-write splitting, redundancy with VIP and Keepalived and more.

ClusterControl Developer Studio: creating advisors using the MySQL performance schema

Learn how to write an advisor to analyze the MySQL performance schema and discover unused indexes and tables referenced without indexes.

Troubleshooting Galera Cluster Issues: Part 2

This is part 2 of our blog on how to troubleshoot Galera cluster - SST errors, and problems with network streaming. In part 1 of the blog, we covered issues ranging from node crashes to clusters that won’t restart, network splits and inconsistent data. Note that the issues described are all examples inspired from real life incidents in production environments.

Troubleshooting Galera Cluster Issues: Part 1

In this blog post, we are going to show you some examples of things that can go wrong in Galera - inexplicable node crashes, network splits, clusters that won’t restart and inconsistent data. We’ll take a look at the data stored in log files to diagnose the problems, and discuss how we can deal with these.

Using NGINX as a Database Load Balancer for Galera Cluster

Nginx is well-known for its ability to act as a reverse-proxy with small memory footprint. It usually sits in the front-end web tier to redirect connections to available backend services, provided these passed some health checks. Using a reverse-proxy is common when you are running a critical application or service that requires high availability. It also distributes the load equally among the backend services.

Understanding the MySQL Galera Cluster and MariaDB Cluster Diagnostic Logs

In a Galera cluster, whether you use MariaDB Cluster, Percona XtraDB Cluster or the Codership build, the MySQL error log is even more important. It gives you the same information as MySQL would, but you’ll also find in it information about Galera internals and replication. This data is crucial to understand the state of your cluster and to identify any issues which may impact the cluster’s ability to operate. In this post, we’ll try to make the Galera error log easier to understand.

Optimizer Hints for Faster MySQL Query Execution

MySQL uses a cost-based optimizer to determine the best way to execute a query. It usually does a great job, but not all the time. There are different reasons for that. In some cases, it might not have enough information about the data and plan queries in a non-optimal way.