Large DAS. The days of small raid sets with more than two disk drives installed in datacenter computers is nearly over. The low connectivity cost combined with super scalability will make iSCSI storage the solution for DAS headaches.
Legacy SANs. Many early adapters of SANs may have aged FC gear. Remember FC-AL (arbitrated loop) hubs and single switch sixteen port SANs? These customers probably have well defined workload, and a fairly static environment. It may be that the FC gear is off maintenance and needs to be replaced. It is likely that nobody in their shop even knows how to operate these decrepit artifacts. Considering the fact that there will be almost zero re-use in an upgrade, these customers will be hesitant to invest more closed technologies. The IP connectivity will be a welcome reduction of complexity, if they can be convinced that iSCSI will do the job and survive.
Non-shared NAS. Many NAS users do not require the multi-host access features of the NFS and CIFS protocols. They deployed NAS for the same reasons that we love IP based iSCSI. NAS can be cost effective, flexible, resilient, and scalable. Ask this type of customer if they'd like to have the features of IP connectivity with the flexibility of a host based volume manager. You'll have an iSCSI convert.
This was first published in January 2007