We regularly get questions about how to set up a Galera cluster with just 2 nodes. The documentation clearly states you should have at least 3 Galera nodes to avoid network partitioning. But there are some valid reasons for considering a 2 node deployment, e.g., if you want achieve database high availability but have limited budget to spend on a third database node. Or perhaps you are running Galera in a development/sandbox environment and prefer a minimal setup.

Galera implements a quorum-based algorithm to select a primary component through which it enforces consistency. The primary component needs to have a majority of votes, so in a 2 node system, there would be no majority resulting in split brain. Fortunately, it is possible to add a …

In this blog, we’ll discuss changing the tablespace directory using pt-online-schema-change.

One of the most annoying situations in the life of a DBA is realizing that the disk where the datadir resides is running out of space. If you’re lucky enough to run over an LVM volume or a RAID (depending on the level, though), it is easy to add disk space. But what if you are not that lucky, and your datadir is running on a single disk? Not so funny!

That is the exact situation we recently faced with a customer, for both the master and slave server. When trying to figure out a solution we saw that:

• There was enough space on a different partition within the same server.
• The tables have their own tablespace (innodb_file_per_table = on)
• The MySQL version was …

This release fixes a rare crash as well as a regression bug introduced in 12.3.0.

Changes as compared to SQLyog MySQL GUI 12.3.0 include:

Bug Fixes:

* 12.3.0 introduced a slowness when displaying the saved connections list with a large no. (100+) of saved connections. This is fixed now.
* Fixed a rare crash occurring sometimes when typing in the editor inside an invalid query longer than 128 characters. Auto-complete was at fault.

Downloads: https://www.webyog.com/product/downloads
Purchase: https://www.webyog.com/shop

The post SQLyog MySQL GUI 12.3.1 Released …

Ok, maybe evil is too strong a word, but MySQL can certainly be deceiving.

Ok, maybe evil is too strong a word, but MySQL can certainly be deceiving.

Ok, maybe evil is too strong a word, but MySQL can certainly be deceiving.

In this post, I’ll discuss how to moving VIPs during a failover using Orchestrator.

In our previous post, we showed you how Orchestrator works. In this post, I am going to give you a proof-of-concept on how Orchestrator can move VIPs in case of failover. For this post, I’m assuming the Orchestrator is already installed and able to manage the topology.

Hooks

Orchestrator is a topology manager. Nothing less nothing more. In the case of failover, it will reorganize the topology, promote a new master and connect the slaves to it. But it won’t do any DNS changes, and it won’t move VIPs (or anything else).

However, Orchestrator supports hooks. Hooks are external scripts …

As many of you will know, MySQL Replication has become an instrumental part of scale-out architectures in LAMP environments. MySQL offers plenty of solutions when there is a need to scale out, the most common being to add read replicas. The major bottleneck for our data is generally not so much oriented around writing our data but more around reading it back. Therefore the easiest way to scale MySQL is to add replicas for reading.

We’ve produced a number of resources during the course of this year aimed at helping users to get started with MySQL Replication and/or get more out of their existing setups.

We’ve summarised these resources here in a handy overview, so that you can pick and chose the ones that might be the most relevant to you.

Do check them out and let us know your feedback!

The White Papers The MySQL© Replication Blueprint by Severalnines

This is a great resource for anyone wanting to …

In MySQL 8.0, we are making large changes to the way the MySQL server stores meta data with the introduction of our native data dictionary. As part of these improvements, we have also made changes to the way the server bootstraps.…

This blog post is all about new MySQL 5.7 physical, logical architecture and it’s components.In this blog post, I will try to explain things in flow including data processing and SQL execution in MySQL with the help of diagrams.

Unlike the other databases, MySQL is a very flexible and offers different kinds of storage engines as a plugin for different kinds of needs. Because of this, MySQL architecture and behavior will also change as per the use of storage engines, for example transactional [InnoDB] and non-transactional [MyISAM] engines data storage and SQL execution methods will be different and within the server it will use engine specific components like memory and buffers depending on type storage engine will get used for the SQL operation.
Will discuss more InnoDB, since it’s default and main storage engine for MySQL.

MySQL Physical Architecture: Configuration files: …