{"id":22779,"date":"2023-12-07T06:18:09","date_gmt":"2023-12-07T06:18:09","guid":{"rendered":"https:\/\/www.finoit.com\/?p=22779"},"modified":"2024-01-15T10:04:08","modified_gmt":"2024-01-15T10:04:08","slug":"high-availability-and-disaster-recovery-best-practices","status":"publish","type":"post","link":"https:\/\/www.finoit.com\/articles\/high-availability-and-disaster-recovery-best-practices\/","title":{"rendered":"Building for Resilience: Ensuring High Availability and Disaster Recovery in Your Architecture"},"content":{"rendered":"

Have you ever noticed how negligible the downtimes of large-scale applications like Netflix, Amazon, and Airbnb are? How do these applications stay online and available 24\/7, even during unexpected failures or natural disasters? The answer lies in using high availability, fault tolerance, and disaster recovery strategies on their system architecture platform to provide continued service.<\/p>\n

Technology downtime and business inoperability dissatisfy your customers and can directly impact your revenues. Hitachi Vantara, in one of its studies, \u2018Embracing ITaaS for Adaptability and Growth\u2019<\/a>, reveals that 56% of businesses hamper their revenue due to service unavailability.<\/p>\n

Even a minor gap in your services can create a domino effect on your business, affecting your customer experience (CX), your revenues, and your entire operation. Whether you are a startup founder or looking to improve the existing design of your architecture, building resilient systems with continuous availability, and effective disaster guarantees the reliability and performance of your products and services.<\/p>\n

Designing a Resilient System<\/strong><\/h2>\n

Without a resilient system, your business might have to bear the hefty cost of downtime. The latest reference can be the one-hour downtime of Amazon<\/a>, which cost the company around $72 million and $99 million in sales. Similarly, Facebook lost a substantial <\/a>$100 million because of an extended outage. You can save your business by following a system architecture with High Availability (HA) and Disaster Recovery (DR) which will ensure your customers have continuous access to your services in spite of any technical failure.<\/p>\n

However, HA and DR, being two individual concepts, have deployment strategies that are vastly different, hence the best practices to include them in your application services are also different. Your hired software architect<\/a> can combine these ideas to design a system that ensures reliable system operation, with minimum downtime. In the following part of the article, we will discuss the High Availability (HA) and Disaster Recovery (DR) approaches and the best practices to deploy them in your system architecture.<\/p>\n

A System Architecture with High Availability (HA)<\/strong><\/h2>\n

Continuous availability, aka, High Availability, refers to the uninterrupted accessibility and functionality of your systems and services, regardless of potential failures or maintenance activities. It’s a crucial aspect of a modern software architecture<\/a> that ensures access to your applications or resources without disruption. With this approach in place, your business can uphold customer satisfaction, trust, and business continuity.<\/p>\n

Furthermore, many industries have regulations mandating a certain level of availability to protect consumer data and ensure service reliability. Failure to maintain these necessary availability levels may lead to legal repercussions or penalties. To calculate the percentage of time your system was operable, you can use this formula:<\/p>\n

x = (n \u2013 y) * 100\/n<\/p>\n

Here, \u2018n\u2019 depicts the total number of minutes within a span of 30 days, and y is synonymous with the total number of minutes your service has been unavailable in the same month.<\/p>\n

Although there is no hard and fixed rule to make your system architecture highly available, there are some best practices that you can adopt to ensure you provide uninterrupted services to your customers:<\/p>\n

Data Backups, Recovery, and Replication<\/strong><\/h3>\n

If you want an exemplary process where your services are protected against system failure, it’s essential to have a solid backup and recovery strategy in place. You can store valuable data with proper backups to replicate or recreate them if necessary. Plan for data loss or corruption in advance, as these errors could create issues with customer authentication, damage financial accounts, and harm your business’s credibility within your industry ecosphere.<\/p>\n

Furthermore, to keep up the data integrity, it’s recommended to create a full backup of the primary database and then incrementally test the source server for data corruption. This tactic will become your most crucial ally in the face of a catastrophic system failure.<\/p>\n

Clustering<\/strong><\/h3>\n

Application services are bound to fail at some point, even with the best technology integration. High availability ensures that your application services are delivered regardless of failures. Clustering can provide instant failover application services in the event of a fault. If your system architecture becomes ‘cluster-aware,’ calling resources from multiple servers becomes easier. Additionally, your primary server can fall back to a secondary server if it goes offline.<\/p>\n

Furthermore, a HA cluster includes multiple nodes that provide information via shared data memory grids. This means that any node can be disconnected or shut down from the network, and the rest of the cluster will continue to operate normally as long as at least a single node is fully functional.<\/p>\n

This approach allows each node to be upgraded individually and rejoined while the cluster operates. The high cost of purchasing additional hardware to implement a cluster can be mitigated by setting up a virtualized cluster that utilizes the available hardware resources.<\/p>\n

Network Load Balancing<\/strong><\/h3>\n

If you want to ensure that your application system remains available without interruption, load balancing can help. With this approach in place, traffic is automatically redirected to other servers still working, when one server fails. This not only ensures high availability but also makes it easier to add more servers if needed.<\/p>\n

You can conduct load balancing in two ways:<\/p>\n