Fault Tolerance in Cloud Infrastructure Questions and Answers for Viva

Answer-1: Fault tolerance is the ability of a cloud system to continue operating properly in the event of a failure of some of its components.

Answer-2: It ensures high availability and reliability by minimizing downtime and service disruption.

Answer-3: Redundancy, failover, replication, and load balancing are commonly used techniques.

Answer-4: Redundancy involves duplicating critical components or systems to provide backup in case of failure.

Answer-5: Failover automatically switches to a standby system or component when the primary one fails.

Answer-6: Replication copies data across multiple servers or data centers to prevent data loss.

Answer-7: High availability minimizes downtime, while fault tolerance allows uninterrupted service despite failures.

Answer-8: Hardware failures, network issues, software bugs, and power outages are common causes.

Answer-9: They distribute traffic to healthy servers, preventing overload and isolating failed instances.

Answer-10: It's the ability of a system to reduce functionality rather than failing completely when some components fail.

Answer-11: Self-healing refers to automatic detection and recovery from failures without manual intervention.

Answer-12: Storing data and services across multiple geographic locations to avoid localized failures.

Answer-13: By using multiple data centers, redundant hardware, automatic failover, and monitoring systems.

Answer-14: Monitoring detects faults early, allowing systems to trigger automatic recovery or alert admins.

Answer-15: Synchronous replication updates all copies simultaneously, while asynchronous replication updates backups after the primary.

Answer-16: It spreads resources and services across multiple nodes to avoid single points of failure.

Answer-17: A component whose failure would cause the entire system to fail.

Answer-18: By introducing redundancy, load balancing, and failover mechanisms.

Answer-19: The process of limiting the impact of faults to a small part of the system.

Answer-20: They can automatically restart or replace failed containers and reschedule workloads.

Answer-21: Backups allow data restoration after a failure or disaster.

Answer-22: Failback restores the system to its primary resource after the failed component is repaired.

Answer-23: They are designed to be resilient, stateless, and able to recover quickly from failures.

Answer-24: A design pattern that prevents an application from performing operations likely to fail.

Answer-25: By isolating services, failures in one service do not affect others.

Answer-26: The practice of intentionally introducing failures to test system resilience.

Answer-27: It means data may not be immediately consistent but will become consistent over time.

Answer-28: Multiple power sources that ensure uninterrupted power during failures.

Answer-29: By distributing resources across multiple availability zones to avoid zone-level failures.

Answer-30: A periodic signal sent between components to check if they are operational.

Answer-31: Failover switches to backup during failure, fallback returns operations to primary after recovery.

Answer-32: Through replication, partitioning, and consensus algorithms.

Answer-33: A minimum number of nodes that must agree to perform an operation to maintain consistency.

Answer-34: By automatically adding or removing resources based on demand and failures.

Answer-35: A contract specifying uptime and fault tolerance guarantees by the cloud provider.

Answer-36: Virtual machines can be migrated or restarted on healthy hosts to minimize downtime.

Answer-37: Through health checks or probes that monitor instance health.

Answer-38: A network architecture that includes redundant paths and failover to prevent downtime.

Answer-39: The guarantee that data will not be lost or corrupted over time.

Answer-40: It allows recovery of previous data versions in case of corruption or accidental deletion.

Answer-41: Capturing the state of a system or data at a specific point in time for backup or recovery.

Answer-42: By leveraging managed services with built-in redundancy and automatic retries.

Answer-43: They prevent cascading failures by stopping requests to failing components.

Answer-44: Multiple network connections to ensure connectivity if one interface fails.

Answer-45: By dynamically rerouting traffic to healthy instances and zones.

Answer-46: Designing systems to fail in a way that minimizes damage and service disruption.

Answer-47: By ensuring consistent and repeatable infrastructure setups that reduce human error.

Answer-48: Fault tolerance ensures continuous operation during faults, disaster recovery focuses on restoring operations after major incidents.

Answer-49: Tools like Chaos Monkey, Gremlin, and cloud provider fault injection services.

Answer-50: By duplicating data across multiple disks or locations to prevent data loss.