What are Stubs?

Stubs are placeholders of the original data after it has been migrated to the secondary storage. Stubs replace the archived files in the location selected by the user during the archive. Because stubs are proprietary and static, if the stub file is corrupted or deleted, the moved data gets orphaned. Komprise does not use stubs, which eliminates this risk of disruption to users, applications, or data protection workflows.

Challenges with Stubs

Stubs are brittle. When stubbed data is moved from its storage (file, object, cloud, or tape) to another location, the stubs can break. The storage management system no longer knows where the data has been moved to and it becomes orphaned, preventing data access. Most storage management solutions on the market use client-server architecture and do not scale to support data at massive scale.

Proprietary interface like stubs can be used to make tiered data appear to reside on primary storage, but the transparency ends there. To access data, the storage management system intercepts access requests, retrieves the data from where it resides, and then rehydrates it back to primary storage. This process adds latency and increases the risk of data loss and corruption.

Standards-Based Transparent Data Tiering

A true transparent data tiering solution creates no disruption, and that’s only achievable with a standards-based approach. Komprise Intelligent Data Management is the only standards-based transparent data tiering solution that uses Transparent Move Technology™ (TMT), which uses Dynamic Links that are based on industry-standard symbolic links instead of proprietary stubs.

Learn more about the differences between stubs, symbolic links and Dynamic Links from Komprise.

Read the Komprise Architecture Overview white paper to learn more.