To solve for the multi-attach limitation, Pure developers came up with a very clever solution. They took the existing Purity software and adjusted it to emulate a flash drive. They can then run the drive emulating software on AWS EC2 instances to act as the backend storage. These EC2 drive emulators, known today as Virtual Drives (VDrives), solve the multi-attach limitation. Furthermore, there are various types of EC2 compute instances that have large amounts of extremely low latent NVMe direct attached storage called Instance Store, which make it perfectly suitable to store host data. The only limitation of Instance Store is that it is ephemeral, which means any data residing on Instance Store will be lost if the EC2 VDrive ever shuts down. To solve for this, all data residing on Instance Store is RAID-HA protected and also mirrored onto Amazon S3. This ensures that all customer data is highly available and safely persisted on highly durable storage.