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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 >-
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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