“When your Exchange server goes down”.
Review of four Exchange high-availability products… “Fujitsu/Softek's
Softek Replicator 2.1.2; LeftHand Networks' SAN/iQ Software, Remote IP
Copy Software and NSM 200 SAN Module combination; NSI Software's
Double-Take for Windows 4.3; and XOSoft's WANSync HA Exchange 3.5.2
Build 45.” [MS Exchange Blog]