What does fallback in Teradata protect against?

Fallback in Teradata is a feature that provides protection against AMP (Access Module Processor) failure. When fallback is enabled for a table, Teradata automatically creates a duplicate of the data on a different AMP. This redundancy ensures that if one AMP goes down or experiences a failure, the data can still be accessed from the backup stored on another AMP.

This mechanism is critical in maintaining data availability and system reliability, particularly in large-scale data environments where uptime is essential. Fallback does not specifically address data redundancy in the broader sense, such as creating multiple copies of data for performance optimization or failover outside of AMP failures. It also does not protect against data corruption or user error, as those issues involve different strategies for resolution, such as backups or data recovery methodologies. By focusing on AMP failures, fallback is designed to enhance system resilience and ensure data accessibility even when hardware failures occur.