<<< SSAG::DISK$ARCH2:[NOTES$LIBRARY.SSAG]ASK_SSAG.NOTE;32767 >>> -< Ask the Storage Architecture Group >- ================================================================================ Note 6530.3 How mirror set redundancy is maintained under hardware mirr 3 of 4 OSOV03::KAGEYAMA "Trust, but Verify" 28 lines 2-APR-1997 00:56 -< 0+1 |= striped mirroring >- -------------------------------------------------------------------------------- Thanks for response. > Mylex raid controller (SWXCRs aka KZPSC and KZPSE) will 'move' the > parity around and indeed allow for 'odd' sized groups for 0+1 shadowing. I've looked into RAID Array 200 manual. It describs the above. RAID 0+1 is implemented as Disk1 Disk2 Disk3 -------------- -------------- --------------- Data1 Data2 Data3 Mirror3 Mirror1 Mirror2 -------------- -------------- --------------- Block 0-1 D1 Block 2-3 D2 Block 4-5 D3 Block 4-5 M3 Block 0-1 M1 Block 2-3 M2 Block 6-7 D1 Block 8-9 D2 Block 10-11 D3 Block 10-11 M3 Block 6-7 M1 Block 8-9 M2 ... ... ... So "0+1" can be started from 3 member disks unlike HSOF. Is this the same thing as "Chained Declustering"? This kind of implmentation could be claimed as "0+1"? 0+1 needs not be same as striped mirroring or mirrored striping? - Kazunori