Clustering, replication and high availability in postgresql

Abstract

In today's data-centric world, ensuring the availability, reliability, and resilience of data systems is of great importance. PostgreSQL, an open-source relational database management system, has gained widespread recognition for its robustness and adaptability, adhering to the core principles of ACID (Atomicity, Consistency, Isolation, Durability). As PostgreSQL assumes a central role in the data infrastructure of many organizations, the need to shield data from unexpected disruptions, system failures, and evolving business demands has grown substantially. This thesis explores the complex challenges related to PostgreSQL's clustering, replication, and high availability features. These components are closely linked, creating a comprehensive strategy to enhance PostgreSQL's resilience against various problems, from hardware issues to network disruptions and data corruption. In the field of database management, achieving high availability is not merely an ambitious goal; it is a fundamental business necessity. The core of this research revolves around a comprehensive exploration of PostgreSQL's clustering techniques, replication methods, and high availability strategies. To illustrate these concepts and strategies, we will introduce a sample database scenario. This example database will serve as a practical guide and aid in clarifying the steps involved in designing, executing, and managing a resilient and dependable database environment. The study encompasses a wide range of topics, including: 1. Clustering Technologies: An examination of PostgreSQL's clustering options, encompassing streaming replication, logical replication, and the utilization of tools like pgpool-2 to craft clusters that can adeptly manage failovers and distribute workloads. 2. Data Replication: An exploration of the intricacies of data replication, with a particular focus on synchronous and asynchronous replication methodologies, alongside logical replication. 3. High Availability: An analysis of different ways we can achieve high availability , such as manual promotion, pgpool-2 tool, along with assessments of their applicability in various use cases. 4. Failover and Disaster Recovery: A comprehensive understanding of failover procedures and disaster recovery planning, including aspects like monitoring, detection, and automated failover mechanisms.