For san boot we need to gave the lun id has 0 but where has you dont find
the available address in FA so we will use lun offset which means where has
your next available address in FA is 7 but when you make lun offset 0 then
your host can see has lun0
there are more uses for LUN Offset other than boot from SAN. If you are not using dynamic lun masking and need to connect a host that only support LUN addressed 0-255 (old Redhat for example), you can use LUN Offset to start LUN enumeration for that host from any physical address available on the FA, physical address could be 0FF and higher.