Raid 4

Raid 4

• It will protect against the loss of just one disk per raid group.
• RAID 4 will not "protect against multiple disk failures"  
• If suppose some disk failed in different raid group, there won't be any data loss.

In Raid 4 Required minimum 2 disks required to create one aggregate

One disk for data disk

One disk for parity disk

RAID 4

Example:

filer>Aggr create -r 5 -t raid4 aggr1 10

aggr1 will randomly take 10 disk from spare disk and -r 5 which means each raid group should have 5 disks

it will create two raid group and each raid group have 5 disks.

http://netapplines.blogspot.in/2013/07/when-any-disk-failed-in-netapp-how-its.html

NetApp Raid

RAID-Redundant Array Of Independent Disks

In all the Raid in NetApp having minimum data disk and minimum parity disk
Disk Types

Data      : Holds data stored within the RAID group

Spare    : Does not hold usable data but is available to be added to a RAID group in an aggregate,

                also known as a hot spare

Parity    : Store data reconstruction information within the RAID group

dParity  : Stores double-parity information within the RAID group, if RAID-DP is enabled

These are type of disks in filler

DISK TYPE	RAID-DP	RAID4
ATA/BSAS/SATA                        Maximum	16	7
FC/SAS                         Maximum	28	14
ATA/BSAS/SATA                             Default	14	4
FC/SAS                          Default	16	7
ATA/BSAS/SATA                         Minimum	3	2
FC/SAS                       Minimum	3	2

In Netapp two raid supported

1. Raid4
2. Raid DP

In NetApp default  raid type is Raid Dp.




Please write your valuable comments, About This Blogspot.