Areca ARC-1231ML/1261ML/1280ML manual Disk Write are Duplication, it is also a costly Similar to a

INTRODUCTION

1	Also known as mirroring	2	Lower	Reads	Reads are
	All data replicated on N sepa-		than	are	twice as fast
	rated disks.		RAID 6;	higher	as a single
	N is almost always 2.		Higher	than a	disk;
	This is a high availability solu-		than	single
	tion, but due to the 100%		RAID	disk;	Write are
	duplication, it is also a costly		3, 5		similar to a
	solution. Half of drive capacity in			Writes	single disk.
	array devoted to mirroring.			similar
				to a
				single
				disk
1E	Also known Block-Interleaved	3	Lower	Transfer	Reads are
	Parity.		than	rates	twice as fast
	Data and parity information		RAID 6;	more	as a single
	is subdivided and distributed		Higher	similar	disk;
	across all disks. Parity must be		than	to RAID
	the equal to the smallest disk		RAID	1 than	Writes are
	capacity in the array. Parity		3, 5	RAID 0	similar to a
	information normally stored on a				single disk.
	dedicated parity disk.
3	Also known Bit-Interleaved Par-	3	Lower	Reads	Reads are
	ity.		than	are	close to being
	Data and parity information		RAID 1,	similar	twice as fast
	is subdivided and distributed		1E, 6;	to	as a single
	across all disks. Parity data			RAID	disk;
	consumes the capacity of 1		Higher	0;
	disk drive. Parity information		than a		Writes are
	normally stored on a dedicated		single	Writes	similar to a
	parity disk.		drive	are	single disk.
				slower
				than a
				single
				disk
5	Also known Block-Interleaved	3	Lower	Reads	Reads are
	Distributed Parity.		than	are	similar to
	Data and parity information		RAID 1,	similar	RAID 0;
	is subdivided and distributed		1E, 6;	to
	across all disk. Parity data con-			RAID 0;	Writes are
	sumes the capacity of 2 disk		Higher		slower than a
	drive.		than a	Writes	single disk.
			single	are
			drive	slower
				than a
				single
				disk

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