Codership Tutorials on Galera Cluster

Article Counts: 20 Tutorials; Recent Changes: 2 Revised, 3 New Articles

These are tutorial articles of the training section of the Codership Library. Here you’ll find tutorial articles on how to get started with Galera and other basic tasks related to initially starting a Galera Cluster. There are also some intermediate articles on a few other aspects of Galera and related software.

Getting Started with Galera Cluster

Length: 840 words; Writer: Staff; Pub: Oct 2014

This article explains Galera Cluster, how it works. It provides an overview for installing Galera and initializing nodes in a cluster. It’s a jumping off point to several other tutorials here.

Installing Galera Cluster

Length: 946 words; Writer: Staff; Pub: Oct 2014

This tutorial provides instructions to prepare your servers and instal Galera Cluster on each. When you install Galera, you have to choose between three implementations available.

Installing a Galera Cluster on AWS

Length: 2494 words; Writer: Russell J.T. Dyer; Pub: Jun 2019

This tutorial explains how to use Amazon Web Services (AWS) to create virtual servers for a Galera Cluster: how to install and configure the database and Galera software on each node.

System Configuration

Length: 964 words; Writer: Staff; Pub: Oct 2014

After installing Galera, you’ll need to configure each node. This straightforward article provides a list of parameters to set in each node’s database configuration file.

Replication Configuration

Length: 964 words; Writer: Staff; Pub: Oct 2014

This article provides a guide to configure the database server to connect and communicate with the cluster. It explains the syntax format used in cluster addresses.

Starting the Cluster

Length: 1,097 words; Writer: Staff; Pub: Oct 2014

A cluster requires at least two nodes, but you have to start the first one somehow. You’ll need to bootstrap the Primary Component. This article explains how to initialize the cluster.

Getting Started Galera with Docker

Length: 1416 words; Writer: Erkan Yanar; Pub: May 2015

This article explains how to build a basic Docker Image and deploy it on a test cluster. It also describes how to deploy Galera Cluster over multiple Docker hosts.

Testing a Cluster

Length: 499 words; Writer: Staff; Pub: Oct 2014

Once you have a cluster running, test its features to ensure it’s working well, to decide on a deployment plan. This tutorial provides a guide to testing replication and cluster operations.

Differences from a Stand-Alone MySQL Server

This tutorial provides information on the differences between a Galera Cluster and a Stand-Alone MySQL Server.

Monitoring a Galera Cluster

Length: 2535 words; Writer: Russell J.T. Dyer; Pub: Jul 2019

This tutorial explains how to monitor a Galera Cluster, utilizing the Galera specific status variables, as well as employing scripts for logging status information.

Making Back-Ups with Galera Cluster

Length: 2693 words; Writer: Russell J.T. Dyer; Pub: Nov 2019

Using Galera, there are a few ways to make a back-up. This article looks at back-up basics, methods involving replication, and how to automate back-ups using the Galera functionality.

Debugging Problems with SST

Length: 985 words; Writer: Philip Stoev; Pub: Jul 2015

The entire dataset is transfered (i.e., SST) to a new node and when a node rejoin after being down for a long time. This article offers insights and advice if there are problems with SST.

The Primary Component in Galera Cluster

Length: 782 words; Writer: Philip Stoev; Pub: Aug 2015

This article describes the Primary Component. This is a central concept in how Galera ensures database consistency and no divergence between nodes in case of a network split.

Galera Cluster Migration Factors

Length: 2087 words; Writer: Staff; Pub: Oct 2014

Migrating data with Galera Cluster should be done carefully. This tutorial article will help you to understand the concepts involved and take you through the steps to migrate a database.

Support for Transaction Isolation Levels

Length: 1009 words; Writer: Seppo Jaakola; Pub: Sep 2015

Many DBAs and database developers don’t understand what MySQL transaction isolation levels Galera CLuster supports and how it does so. This articles tries to answer those uncertainties.

To SST or Not To SST?

Length: 1001 words; Writer: Philip Stoev; Pub: Dec 2016

When a node rejoins a cluster, there are two methods of synchronizing it quickly. This article describes the process of doing this and confusing messages one might see in the logs.

Restarting the Cluster

Length: 791 words; Writer: Staff; Pub: Oct 2014

Restarting a cluster so that data isn’t overwritten can be tricky. This article explains how to determine the most up-to-date node, so that it’s the first node of the new cluster.

The Safe-To-Bootstrap Feature

Length: 745 words; Writer: Philip Stoev; Pub: Nov 2016

When it’s necessary to shut down a cluster, it’s important to do so safely and as quickly as possible to avoid extended downtime and data loss. This article gives advice in this area.

Recovering a Galera Node or the Entire Cluster on Ansible

When it’s necessary to recover a cluster node or the entire cluster by using Ansible, this article gives advice in this area.

Read-After-Write Semantics with Galera

Length: 599 words; Writer: Philip Stoev; Pub: Jun 2015

Clients may try to read rows just inserted, excluding it from a transaction. Read/write splitting proxy, or a connection pool and a load balancer, can send queries to other nodes.

Geo-Distributed Database Clusters

Length: 1043 words; Writer: Philip Stoev; Pub: Oct 2014

Nodes may be located in multiple physical locations. This article presents the benefits of a geo-distributed cluster, and Galera specific features to enable replication across a WAN.

Debugging Transaction Conflicts

Length: 1,086 words; Writer: Philip Stoev; Pub: Jun 2015

When using Galera in multi-primary mode, transaction conflicts may occur if clients try to modify the same row at the same time. This discusses troubleshooting these deadlock errors.