Home > Data Protection > PowerProtect DD Series Appliances > PowerProtect DD Data Invulnerability Architecture: Enhancing Data Integrity and Recoverability > Conclusion
No single mechanism is sufficient to ensure data integrity in a storage system. Data recoverability can be assured only through the cooperation of a multitude of mechanisms that establish successive lines of defense against all sources of errors.
Unlike a traditional storage system that has been repurposed from primary storage to data protection, PowerProtect DD systems have been designed explicitly as the data store of last resort. The innovative Data Invulnerability Architecture offers the industry’s best defense against data integrity issues. Advanced verification ensures that new backup and archive data is stored correctly. The no-overwrite, log-structured architecture of the Data Domain file system, together with the insistence on full-stripe writes, ensures that old data is always safe even in the face of software errors from new data. Meanwhile, a simple and robust implementation reduces the chance of software errors in the first place.
All these mechanisms protect against problems during the storage of backup and archive data, but faults in the storage itself also threaten data recoverability. For this reason, the Data Invulnerability Architecture includes a proprietary implementation of RAID 6. It protects against up to two disks failures, can rebuild a failed disk even if there is a data read error, and immediately corrects errors during read. The architecture also includes a background scrub process that actively seeks out and repairs latent faults before they become a problem.
The recoverability features of the Data Domain file system provide the final line of defense. The self-describing data format enables the reconstruction of file data even if various metadata structures are corrupted or lost. With the fast file system check and repair, even a system holding dozens of terabytes of data will not be offline for long if a problem occurs. Data Domain systems are the only solution built with this relentless attention to data integrity, giving you ultimate confidence in recoverability.