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Displaying posts with tag: mysql replication (reset)
MariaDB OpenWorks was an ocean of Galera Cluster activity

MariaDB OpenWorks happened February 25-27 2019 in New York City, and it was filled with a lot of activity.

The keynote by Michael Howard is an interesting watch, one with many quoted articles especially around “strip-mining open source technologies and companies,” and “abusing the license and privilege, and not giving back to the community.” Many articles were written about this topic, and it is clear that open source has arrived considering all the success around the IBM acquisition of Red Hat, the Elastic IPO, the Microsoft acquisition of GitHub, the SalesForce acquisition fo MuleSoft and the MongoDB IPO.

Seppo Jaakola talked about …

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Galera Cluster 4 available for use in the latest MariaDB 10.4.3 Release Candidate!

The much anticipated release of Galera 4 makes its way first in the latest release of MariaDB Server 10.4.3 Release Candidate which you can download now. Congratulations to MariaDB Corporation and MariaDB Foundation on this release candidate — please get testing Galera 4, and share your feedback with us via our Google Group discussion list! Do not forget that you can always reach us via email: mailto:info@galeracluster.com and via our contact us form.

The feature we are excited about the most, is a feature request from many users. This is none other than huge transaction …

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MySQL Tutorial – Understanding The Seconds Behind Master Value

In a MySQL hosting replication setup, the parameter Seconds_Behind_Master (SBM), as displayed by the SHOW SLAVE STATUS command, is commonly used as an indication of the current replication lag of the slave. In this blog post, we examine how to understand and interpret this value in various situations.

Possible Values of  Seconds Behind Master

The value of SBM, as explained in the  MySQL documentation, depends on the state of the MySQL slave in general, and the states of MySQL slave SQL_THREAD and IO_THREAD in particular. While IO_THREAD connects with the master and reads the updates, SQL_THREAD applies these updates on the slave. Let’s examine the possible values of SBM during different states of the MySQL Slave.

When SBM Value is Null

  • SBM is …
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How to manually decrypt an encrypted binary log file

The encrypted binary log file format introduced in MySQL version 8.0.14 was designed to allow a “manual” decryption of the file data when the value of the key that encrypted its file password is known.

Each encrypted binary (or relay) log file is composed by an encrypted binary log file header and the encrypted binary log content (the file data).…

Binary log encryption at rest

Starting in version 8.0.14, MySQL server can encrypt all new binary and relay log files on disk. In order to do so, you just need to enable the new binlog_encryption option (and also ensure that you have a keyring).…

MySQL High Availability Framework Explained – Part II

In Part I, we introduced a High Availability (HA) framework for MySQL hosting and discussed various components and their functionality. Now in Part II, we will discuss the details of MySQL semisynchronous replication and the related configuration settings that help us ensure redundancy and consistency of the data in our HA setup. Make sure to check back in for Part III where we will review various failure scenarios that could arise and the way the framework responds and recovers from these conditions.

What is MySQL Semisynchronous Replication?

Simply put, in a MySQL semisynchronous replication configuration, the master …

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Extending replication instrumentation: an insight on transaction retries

MySQL 8.0.13 improves replication lag monitoring by extending the instrumentation for transaction transient errors. These temporary errors, which include lock timeouts caused by client transactions executing concurrently as the slave is replicating, do not stop the applier thread: instead, they cause a transaction to retry.…

MySQL Replication Notes


The MySQL Replication was my first project as a Database Administrator (DBA) and I have been working with Replication technologies for last few years and I am indebted to contribute my little part for development of this technology. MySQL supports different replication topologies, having better understanding of basic concepts will help you in building and managing various and complex topologies. I am writing here, some of the key points to taken care when you are building MySQL replication. I consider this post as a starting point for building a high performance and consistent MySQL servers.  Let me start with below key points Hardware. MySQL Server Version MySQL Server Configuration Primary Key Storage Engine I will update this post with relevant points, whenever I get time. I am trying to provide generic concepts and it will be applicable to all version of MySQL, however, some of the concepts are new and applicable to latest versions …

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Global Read-Scaling using Continuent Clustering

Did you know that Continuent Clustering supports having clusters at multiple sites world-wide with either active-active or active-passive replication meshing them together?

Not only that, but we support a flexible hybrid model that allows for a blended architecture using any combination of node types. So mix-and-match your highly available database layer on bare metal, Amazon Web Services (AWS), Azure, Google Cloud, VMware, etc.

In this article we will discuss using the Active/Passive model to scale reads worldwide.

The model is simple: select one site as the Primary where all writes will happen. The rest of the sites will pull events as quickly as possible over the WAN and make the data available to all local clients. This means your application gets the best of both worlds:

  • Simple deployment with no application changes needed. All writes …
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Mastering Continuent Clustering Series: Global Clustering with Active/Active Meshed Replication

Did you know that Continuent Clustering supports having clusters at multiple sites world-wide with active-active replication meshing them together?

Not only that, but we support a flexible hybrid model that allows for a blended architecture using any combination of node types. So mix-and-match your highly available database layer on bare metal, Amazon Web Services (AWS), Azure, Google Cloud, VMware, etc.

The possibilities are endless, as is the business value. This strong topology allows you to have all the benefits of high availability with local reads and writes, while spreading that data globally to be accessible in all regions. Latency is limited only by the WAN link and the speed of the target node.

This aligns perfectly with the distributed Software-as-a-Service (SaaS) model where customers and data span the globe. Applications have access to ALL the …

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