f5771a61_12__Storage_Subsystem___Part_2__1
[0] · Spanning [1] 
Not a RAID level. Spannig is the concatenation of multiple physical disks into a single logical disk. Each disk contains one continuous set of sequential logical blocks. Spanning has the same performance and reliability characteristics as a JBOD configuration.
Performance Tuning Windows 2012: Storage Subsystem - Part 2
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