Fibre Channel storage arrays generally come in two flavors: single and dual controller storage arrays.
Single controller storage arrays are the easiest to understand and configure. The single controller is responsible for all the reads and writes to the attached disks. Storage array shelves are attached to the controller with P2P Fibre Channel connections. Some storage arrays will connect to the single controller using dual FC connections. Single controller storage arrays can withstand FC link failures when configured correctly but are unable to withstand controller failures. If a single controller storage array needs a firmware update or to fix a problem with the storage controller, the whole array must be taken out of production duty. VMware storage vMotion can be utilized to migrate data off the single storage array when planning for an outage. Unfortunately, in the case of an unplanned outage, we may end up with stranded data...