Redundancy

Ensuring backup systems are in place to prevent failure.

Also Known As

• Backup
• Failover
• Load Balancing (in DevOps)
• Redundancy (in DevOps)
• Resilience
• Stockpiling

Related

• Incident Management
• Pair Programming

Addresses / Mitigates

• Reliability Risk: Minimizes operational disruptions by providing backup components.
• Security Risk: Enhances security by providing alternative paths and systems.
• Unintended Cascading Failures: Implementing backup mechanisms to prevent systemic failures from spreading across interconnected systems.

Attendant Risks

• Complexity Risk: Introducing redundancy can add complexity to the system.
• Funding Risk: Implementing redundancy can be expensive.

Used By

• DevOps: Load balancing and redundancy are crucial for maintaining uptime in a DevOps environment.

Description

"Redundancy is the duplication of critical components or functions of a system with the intention of increasing reliability of the system, usually in the form of a backup or fail-safe, or to improve actual system performance." - Redundancy (engineering), Wikipedia

Redundancy in engineering is a key practice to ensure that systems remain operational in the event of component failures. It involves creating multiple instances of critical components so that if one fails, the others can take over seamlessly. This practice is essential in systems where reliability and availability are critical, such as in data centers, aerospace, and power systems. Implementing redundancy helps in maintaining service quality and availability, thereby reducing the risk of operational disruptions.

Variations

Redundancy Type	Description	Reference
Active-Passive Failover	A standby system takes over when the primary system fails.	Failover, Wikipedia
Active-Active	Multiple systems share the load simultaneously, providing both redundancy and capacity.	High Availability Cluster, Wikipedia
Geographic Redundancy	Distributing systems across multiple physical locations to survive regional failures.	Disaster Recovery, Wikipedia
Data Replication	Maintaining copies of data across multiple storage systems or locations.	Replication, Wikipedia

Used By

DevOps

A set of practices that combines software development (Dev) and IT operations (Ops) to shorten the development lifecycle and provide continuous delivery with high software quality.

Why: Load balancing and redundancy are crucial for maintaining uptime in a DevOps environment.

Uses:

• Load Balancing
• Redundancy