a “ lun table ” enables logical unit number mapping / masking within an input / output virtualization iov adapter included in a serial attached small computer system interface . a plurality of system images share block storage through the sas . the iov adapter includes one or more virtual functions , a physical function , and a lun table within the pf . the vf allows each si to communicate i / 0 requests with a storage device through the pf . the lun table maps the i / 0 requests to unique locations within the storage device . each si is isolated from all other sis . interference between each si is avoided . a vios or a lun mapping / masking san are not required . i / 0 latency , processor overhead and storage cost are improved over prior lun mapping / masking solutions .