High Availability

Ahmad Yaseen
SQL Server Always on Failover Cluster topography

SQL Server Transaction Log and High Availability Solutions

March 21, 2019 by

In the previous article of this series on the SQL Server transaction log, we discuss the SQL Server database recovery models, Full, Simple and Bulk-Logged, and the how the recovery model option of the database affects the way the SQL Server Engine works with the transaction logs. In this article, we will discuss the different types of high availability and disaster recovery solutions and the role of the SQL Server transaction log in these technologies.

Sreekanth Bandarla
Add Roles and Features Wizard - Remote access

Simulating a Multi Subnet cluster for setting up SQL Server Always On Availability Groups – lab setup

March 14, 2019 by

In this article, we are going to see how to create a multi subnet cluster spanning across multiple subnets for lab purposes. Creating such an environment should help creating Availability groups simulating a far replica residing in a different Data Center (Subnet) acting as a disaster recovery site in your lab for learning/experimenting real world scenarios.

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Sreekanth Bandarla

Deploy SQL Server with Cluster Shared Volumes – part 2

September 19, 2018 by

In the other article in this series: Deploy SQL Server for failover clustering with Cluster Shared Volumes – part 1 we have seen what a cluster shared volume is and what are the advantages and other considerations to keep in mind when deploying CSVs for SQL Server workloads. In this article, I will walk though actual installation of a failover cluster Instance leveraging CSVs.

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Sreekanth Bandarla

Deploy SQL Server for failover clustering with Cluster Shared Volumes – part 1

September 4, 2018 by

Microsoft SQL Server provides us with a wide variety of solutions to architect High availability (HA) and Disaster Recovery (DR) solutions for mission-critical workloads. In this article, let’s just focus on HA, specifically Failover Clustering. Failover clustering is probably the most mature, robust and stable high availability solution which Windows Server Operating system offers. It’s been there around for few decades now and did evolve over time along with SQL Server. In this article Let’s see a hidden feature of windows server failover cluster which helps in making our already highly available SQL Server Failover clustered instances even more highly available. The new feature which we are going to talk about is Cluster Shared Volumes, AKA CSVs. Considering windows server 2019 is around the corner, I say CSVs are not a new concept in clustering, it’s been there for almost a decade now. Microsoft introduced CSVs in windows server 2008R2, but at that time SQL Server was not supported on CSVs. Well, CSVs were originally designed for Hyper-V workloads and later on enhanced for File servers and eventually landed into SQL Server beginning version 2014.

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Daniel Calbimonte

How to create a Database Mirroring

March 6, 2015 by

Sometimes our Database fails and we need to reestablish the Database services immediately. Is there a SQL Server solution for high availability?

With Database Mirroring, we can have a replica of the database ready to be used if the main database fails. In this article, we will give a step-by-step tutorial about Database Mirroring. There are other solutions for high availability like high AlwaysOn, Clusters and Log Shipping, but in this chapter, we will start with Mirroring.

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Derik Hammer

Disaster Recovery Planning with Always-On Availability Groups

December 17, 2014 by

When I configured my first Always-On Availability Group, I setup a Windows Cluster and started with SQL Server Management Studio’s New Availability Group Wizard, scripting out the steps along the way. This entire process took only a matter of minutes. The minimum required steps for configuring the cluster and getting a database into an Availability Group (AG) are very few. This process, however, is deceptively simple. What some don’t realize is that the majority of work required for setting up an AG needs to occur in the planning phase, before a server is even requisitioned. Let us examine the questions that you should ask before implementing an AG.

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Ivan Stankovic

What is SQL Server database mirroring?

March 15, 2014 by
SQL Server database mirroring is a disaster recovery and high availability technique that involves two SQL Server instances on the same or different machines. One SQL Server instance acts as a primary instance called the principal, while the other is a mirrored instance called the mirror. In special cases, there can be a third SQL Server instance that acts as a witness Read more »