Fault tolerance- refers to the ability of a system (like a computer, network, or software) to continue functioning properly even when one or more components fail. It's a critical concept in computing, particularly in networks, cloud computing, and large systems, where failure of parts of the system is inevitable.
Key Concepts of Fault Tolerance:
1. Redundancy: Adding extra components (like multiple power supplies, servers, or network paths) to ensure that if one component fails, another takes over.
2. Replication: Keeping multiple copies of data or processes so that if one fails, others can continue the task without losing data.
3. Failover: Automatically switching to a backup system when a failure occurs.
4. Error Detection and Correction: Mechanisms that detect errors or failures and either correct them or alert the system to take action.
5. Graceful Degradation: Instead of completely failing, the system reduces its functionality while maintaining some operation.
Examples:
RAID storage: Using multiple hard drives where data is spread across them, so if one fails, the others maintain data integrity.
Backup Power (UPS): Ensures that systems continue to function during a power outage.
