This article provides an in-depth exploration of quorum loss in Windows Failover Clusters and its impact on SQL Server Always On Availability Groups. It explains how nodes communicate using heartbeat packets, the process of handling failed heartbeats, and the rejoining of nodes to the cluster. The post also outlines various quorum voting configurations and their implications for cluster stability and data integrity. Additionally, it discusses the importance of maintaining quorum for high availability and disaster recovery in SQL Server environments.
Category: Availability Groups
Creating SQL Server AGs on Linux: Part 3 – Pacemaker Resources and Constraints
Welcome to the third part of our series on setting up SQL Server availability groups on Linux. In the previous post, we focused on enabling High Availability Disaster Recovery (HADR) on SQL Server and setting up the availability group. This post will guide you through configuring Pacemaker resources and constraints to manage the availability group effectively.
Creating SQL Server AGs on Linux: Part 2 – Enabling HADR on SQL Server
This is part of a series on setting up SQL Server availability groups on Linux. It details how to enable High Availability Disaster Recovery (HADR) on SQL Server, including creating master keys, certificates, and availability groups. Clear instructions are provided for configuring SQL Server and Pacemaker to ensure data redundancy and high availability. Follow these steps to enhance the reliability of your SQL Server instances on Ubuntu 20.04.
Creating SQL Server AGs on Linux: Part 1 – Installing and Configuring Pacemaker
This post is the first part of a series on setting up SQL Server availability groups on Linux. It covers the installation and configuration of Pacemaker on Ubuntu 20.04, creating the Pacemaker cluster, and configuring essential cluster properties. Designed for SQL Server DBAs with limited Linux experience, this guide lays the foundation for a robust high availability environment.
SQL Server AG Readonly Secondaries and their Associated Overhead
In SQL Server Always On Availability Groups, configuring read-access for one or more secondary replicas introduces additional overhead to the primary databases. This overhead, specifically a 14-byte addition to modified, inserted, or deleted data rows, is essential for the row versioning feature that ensures data consistency across replicas. Row versioning allows secondary replicas to perform read operations without being affected by ongoing changes on the primary replica, ensuring a consistent view of the data. Understanding this overhead and its impact on storage and performance is crucial for optimizing SQL Server environments.
SQL Auditing and Always On: Working Together
Maintaining continuous and consistent auditing is crucial for security, compliance, and troubleshooting. When working with SQL Server Always On Availability Groups, a failover event can pose significant challenges to your audit configurations and logs. This guide will help you navigate these challenges by outlining the key considerations and steps necessary to ensure that SQL Server auditing remains seamless during a failover.
Understanding In-Memory Tables with Always On in SQL Server
In today’s dynamic database management landscape, achieving high performance and reliability is paramount. SQL Server’s Always On availability groups offer a robust framework for high availability and disaster recovery. When combined with the power of in-memory tables, the capabilities of your SQL Server deployment are significantly amplified. This blog explores the benefits of using in-memory tables with Always On availability groups and demonstrates how these technologies can work together to optimize performance and ensure reliability in your SQL Server environment.
Enhancing Data Loading Performance in SQL Server Availability Groups
Learn essential strategies for managing data loading performance in SQL Server, focusing on techniques such as reducing batch sizes and understanding the impact of transaction sizes. This blog provides practical insights and examples to optimize performance and scalability, particularly in environments utilizing Availability Groups.
Exploring READ_WRITE_ROUTING_URL in SQL Server AlwaysOn Availability Groups
This blog post explores the READ_WRITE_ROUTING_URL parameter in SQL Server AlwaysOn Availability Groups. It explains how this feature helps optimize read/write traffic and improve performance by routing connections based on their intent (read-write vs. read-only). The post also includes a practical example demonstrating connection routing behavior and concludes with additional considerations for security and monitoring.
Worker Threads in SQL Server Always On Availability Groups
Explore the role of worker threads in SQL Server Always On Availability Groups. This post covers how worker threads function, their management, and the impact on database availability and performance, with practical tips on calculating and monitoring thread usage to optimize your SQL Server configurations.