Xsan

Xsan is a cluster file system for Mac OS X. Its primary use is to allow multiple hosts to access multiple Xserve RAIDs with the use of a fibre channel switch.

Release history
Apple Inc. first announced Xsan in 2004.
 * Xsan 1.0 began shipping on January 4, 2005.
 * Xsan 1.2 shipped in May 2006.
 * Xsan 1.4 shipped on August 7, 2006.
 * Xsan 2 shipped on February 19, 2008 with MultiSAN.
 * Xsan 2.3 shipped on July 20, 2011 with Mac OS X 10.7 Lion
 * Xsan 3 shipped on July 25, 2012 with OS X 10.8 Mountain Lion
 * Xsan 4 shipped on October 17, 2014 with OS X 10.10 Yosemite
 * Xsan 5 shipped on September 20, 2016 with macOS 10.12 Sierra