Current industry trends involve some type of secondary volume copy of a disk's primary volume, typically because only one copy is active at a time. Depending on recovery time and recovery point objectives, common solutions involve either host based replication software or storage based solutions such as snapshot and mirroring.

1. Overland REO Multi-Site Pac
2. Lefthand Campus SANIQ Cluster
3. Dell EqualLogic's SAN Auto-Replicator

1. Bakbone Netvault Replicator
2. Sonasoft Sonasafe DR Solution