# How to Determine the RAID1 vDisk Mirror Disk Pairs in a Storage[TM] 2500 and 6000 Array (Doc ID 1020837.1)

Last updated on JULY 24, 2019

## Applies to:

Sun Storage 2530-M2 Array - Version Not Applicable to Not Applicable [Release N/A]
Sun Storage 2540-M2 Array - Version Not Applicable to Not Applicable [Release N/A]
Sun Storage 6140 Array - Version Not Applicable to Not Applicable [Release N/A]
Sun Storage 6580 Array - Version Not Applicable to Not Applicable [Release N/A]
Sun Storage 6780 Array - Version Not Applicable to Not Applicable [Release N/A]
All Platforms

## Goal

The intent of this document is to explain how RAID 1 are built in the array and how to determine the mirror pairs.

In a RAID 1+0 Virtual Disk (vdisk) the disks are mirrored using the following algorithm:

Data drive = X
Mirrored drive = N/2+X

where:
- N is the total number of physical disks.
- X goes from 1 to N/2

For example, if you have six physical disks (1, 2, 3, 4, 5, 6) the mirror pairs are:

Mirrored disks:

For disk 1: 6/2+1= disk 4
For disk 2: 6/2+2= disk 5
For disk 3: 6/2+3= disk 6

The first disk of the first half is mirrored to the first disk of the second half, the second disk of the first half is mirrored to the second disk of the second half, etc, up to the last disk of the first half is mirrored to the last disk of the second half.