ExaGrid

ExaGrid provides tiered backup storage in which each appliance contributes disk, memory, bandwidth and processing power, so capacity and performance scale together. Its architecture combines a disk-cache landing zone for recent backups with a longer-term deduplicated retention repository, in a scale-out arrangement.

The landing zone is the design decision the whole product rests on and it addresses the trade every deduplication system makes. Deduplicating data as it arrives saves space and slows both backup and restore, whereas writing to undeduplicated disk first keeps the backup window short and the most recent restore fast, with deduplication happening afterward.

Restores are what actually matter and are frequently the thing nobody tests. A backup system is judged in the hour after a failure, and recent backups sitting on plain disk rather than needing reconstruction from deduplicated blocks is the difference between a quick recovery and a long one.

Adding processing power with each appliance rather than only capacity is what keeps that true at scale. Systems where storage grows but the controller does not become slower as they fill, which is precisely when a backup environment is under most pressure.