User guide

43MAXDATA SR1202 M1 – StorView

RAID User Guide

7 Conﬁguring a Storage Solution

Creating Disk Arrays

Configuring a storage solution requires some planning to ensure that you define the correct RAID

level and array options, hot spares and logical drives for your solution requirements.

This chapter will step you through the process to configure and manage your disk arrays, assign hot

spares and create the logical drives.

This manual assumes you have a basic understanding of RAID concepts.

RAID Levels

The following are the drive requirements for each supported RAID level.

Table 1. Drive Requirements by RAID Level

RAID Level Minimum No. of Drives Maximum No. of Drives

0 1 16

1 2 16

5 3 16

50 6 16

4 16

Terminology

The following describes some of the terminology used when creating disk array’s and logical

drives.

Term Description

Array A group of disk drives that are combined together to create a single large

storage area. Up to 64 arrays are supported, each containing up to 16

drives per array. There is no capacity limit for the arrays.

Back-off Percent In order to allow drives from a different family or manufacturer to be used

as a replacement for a drive in an array, it is recommended that a small

percentage of the drive’s capacity be reserved when creating the array.

This is user selectable, from 0 to 10 percent. This is sometimes known as

Reserved Capacity.

Cache Flush Array This is the array that is used to automatically flush cache data in a situation

where power has failed to some of the drives.

Chunk Size This is the amount of data that is written on a single drive before the

controller moves to the next drive in the stripe.

Initialization RAID 5/50 arrays must have consistent parity before they can be used to

protect data. Initialization writes a known pattern to all drives in the array.

If the user chooses not to initialize an array, the array will be trusted. Any

drive failure will result in data corruption in a trusted array. (It is possible

to later perform a parity rewrite, which recalculates the parity based on the

current data, thus ensuring the data and parity are consistent.)

Logical Drive Avail

ability

To accommodate hosts with multiple ports and multiple host systems, it

is possible to restrict a logical drive’s availability to a particular HBA or

controller port. Access can be enabled or disabled for each host port of

each controller.