iSCSI SANs don't have to suck
Derek J. Balling · USENIX Large Installation Systems Administration Conference · 2010
We have created a iSCSI SAN architecture which permits maintenance of network components without any downtime, thus improving our ability to maintain the SAN beyond iSCSI's mediocre reputation. We currently use this system to provide web-based services for all of Answers.com. During development of this architecture we learned three important lessons: Packet loss/congestion is absolutely fatal. Network design must be smart about Spanning Tree events, and a separate network, not separate VLANs, is required. Forethought in design creates a system that is highly maintainable, permitting an isolate and swap methodology for upgrades and maintenance.