3PAR InForm® OS 2.3.1 Concepts Guide (320-200112 Rev B, February 2010)

InForm OS Version 2.3.1 3PAR InForm OS Concepts Guide

8.1

Logical Disks

In this chapter

8.1 Overview 8.1

8.2 Logical Disks and Common Provisioning Groups 8.2

8.3 Logical Disk Types 8.2

8.4 RAID Types 8.3

8.5 Logical Disk Size and RAID Types 8.8

8.6 Logical Disk Size and Virtual Volumes 8.9

8.7 Logical Disk Size and Common Provisioning Groups 8.9

The purpose of this chapter is to explain the relationship between logical discs, RAID types, and

other InServ Storage Server data layers.

8.1 Overview

A Logical Disk (LD) is a collection of physical disk chunklets arranged as rows of RAID sets. Each

RAID set is made up of chunklets from different physical disks. Logical disks are pooled

together in Common Provisioning Groups (CPGs) which allocate space to virtual volumes.

Creating CPGs maps out the data layout parameters for the eventual creation of logical disks.

Logical disks are created when volumes are created from the CPGs. The RAID type, space