Continuing on from Setting up Galera Load Balancer (GLB), wouldn’t it be nice to ensure that Galera Load Balancer (GLB) handles failover, seamlessly?

Router:
------------------------------------------------------
        Address       :   weight   usage    map  conns
188.166.179.177:3306  :    1.000   0.500    N/A      1
  165.22.50.152:3306  :    1.000   0.500    N/A      1
   165.22.49.92:3306  :    1.000   0.000    N/A      0
------------------------------------------------------
Destinations: 3, total connections: 2 of 493 max

Pool: connections per thread:     1     1     0     0     0     0

Here is an example of a Galera Load Balancer (GLB) handling 3 backend MySQL servers, and it currently has 2 connections, evenly distributed between 2 hosts.

We can verify this by doing: select @@hostname; which shows:

MySQL now supports the INTERSECT and EXCEPT set operators. Set operators work on the results of multiple SELECT statements. In this post, we will see example queries using INTERSECT and EXCEPT commands for a better understanding

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While MySQL has supported UNION and UNION ALL commands, there were no INTERSECT or EXCEPT commands in the language. This often involved work-around queries. However, MySQL now does support the INTERCEPT and EXCEPT set operators.

For the example queries, I am using 2 simple tables with arbitrary data.

The names …

Codership is pleased to announce a new Generally Available (GA) release of the multi-master Galera Cluster for MySQL 5.7, consisting of MySQL-wsrep 5.7.38 (release notes, download). This release incorporates all changes to MySQL 5.7.39, adding a synchronous option for your MySQL High Availability solutions.

We have backported the InnoDB wsrep applier lock wait timeout from 8.0 which introduces the variable innodb-wsrep-applier-lock-wait-timeout to improve the reliability in resolving …

Anyone operating a blog, newsletter, or other creative side hustle knows there are a lot of moving pieces involved behind the scenes. Keeping the cadence going not only requires commitment and skills, but also various tools and software…

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At the time of writing, the OpenLampTech developer newsletter is entering its 10th straight month of publishing so I thought it was time to share a ‘Tools of the Trade – …

Galera Load Balancer (GLB) is a scalable and performant, yet easy to use TCP/IP connection balancing proxy. It is the oldest, yet actively maintained load balancer in the MySQL ecosystem, with a wide array of customers using it in production.

Firstly, please request for binaries via contacting sales@galeracluster.com. Once you have access to the package repository, you’ll have access to RPMs. Installing the RPMs are straightforward, and you can also add it to your Yum repository. This blog presumes you already have access to the binaries.

You can start it up, really simply:

glbd --threads 6 127.0.0.1:3306 188.166.179.177:3306 165.22.50.152:3306 165.22.49.92:3306 …

A few things we have noticed recently when it comes to Galera Manager support requests, that we feel we should address in this blog post.

First and foremost, it is a requirement that you install Galera Manager on a clean host. This means you install the base operating system and nothing else: no Nginx, no Apache, no InfluxDB, etc. The Galera Manager installer (gm-installer) will pull all the requisite packages, set SELinux to permissive during the install, etc. The next release of the gm-installer aims to be less fragile when it comes to this, and will aggressively handle installs on machines that already have software installed on it.

The other common issue is the inability to access ports, generally blocked by a firewall (gm-installer should have fixed this as long as setup is going properly), or some other reason. What gm-installer cannot fix …

Codership is pleased to announce a new Generally Available (GA) release of the multi-master Galera Cluster for MySQL 5.7, consisting of MySQL-wsrep 5.7.38 (release notes, download). This release incorporates all changes to MySQL 5.7.38, adding a synchronous option for your MySQL High Availability solutions.

In MySQL 5.7.38, we now distinguish between unset ssl_mode and ssl_mode explicitly set to “DISABLED”, because previously ssl_mode=DISABLED was ignored in the xtrabackup-v2 script.

This is a rare release where you are also meant to continue using the Galera replication library 3.37 implementing the wsrep API version 25, from the previous release, as there was no changes made to the Galera replication …

A few weeks ago, we did a Galera Cluster webinar on Managed Galera Clusters on DigitalOcean.

Some of you may notice that the current version of Galera Manager is 1.6.4, and one of the major fixes we have in there is to support the new API token format of DigitalOcean. DigitalOcean has documented this here: Updated API Tokens new management features: in partnership with GitHub –Secret Scanning, Prefixes, and more! and as a consequence we needed to update to accept new API tokens, or it would fail in deployment. If you’re wondering how to create a …

We don’t always need all rows from the table as part of the final results set. You can use one (or more) of the comparison operators to filter the rows with a WHERE clause conditional. In this post, we are looking at the equality comparison operator (=)…

The Newsletter for PHP and MySQL Developers

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Image by kalhh from  …

The MySQL DATE() function is a built-in function you use to extract just the date portion from a DATE or DATETIME value. Learn how to use the DATE() function in this blog post…

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MySQL DATE() Function Syntax

The …