How to configure a RAID 5

Posted on 2006-04-29
Last Modified: 2010-04-03
I am trying to configure 3 SCSI drives on a Poweredge 4300 to be RAID 5.

I have a PERC SCSI Controller. I have updated the firmware.

I go into the PERC BIOS and configure a NEW CONFIGURATION.

I then select each of the 3 SCSI drives which are 8GB each.

I then press enter to END the ARRAY.

I then see that the size of the logical drive is only 16BG.

Why is is only 16BG and not 24BG? ( 3*8 = 24 and 2*8 = 16)

Question by:mancoi
    LVL 95

    Expert Comment

    by:Lee W, MVP
    Because RAID 5 uses one disk worth of space for parity information.

    You will only get (Drives) x (smallest disk size) - (smallest disk size) space available when using RAID 5.
    LVL 95

    Accepted Solution

    So if you had 10x8GB drives you would have 9x8GB space available.
    LVL 95

    Expert Comment

    by:Lee W, MVP

    Write Comment

    Please enter a first name

    Please enter a last name

    We will never share this with anyone.

    Featured Post

    Top 6 Sources for Identifying Threat Actor TTPs

    Understanding your enemy is essential. These six sources will help you identify the most popular threat actor tactics, techniques, and procedures (TTPs).

    Hi, I've made you some graphics for a better understanding how RAID works. First of all, there are two ways a raid can be generated: - By hardware - By software What does that mean? This means: If you have a hardware RAID controller, there…
    In this article, I provide some information on storage disks which go into calculations that will help you figure out how much Input/output Operations Per Second (IOPS) your disk subsystem can deliver. To effectively size & tune up applications l…
    This video teaches viewers how to encrypt an external drive that requires a password to read and edit the drive. All tasks are done in Disk Utility. Plug in the external drive you wish to encrypt: Make sure all previous data on the drive has been …
    This Micro Tutorial will teach you how to reformat your flash drive. Sometimes your flash drive may have issues carrying files so this will completely restore it to manufacturing settings. Make sure to backup all files before reformatting. This w…

    779 members asked questions and received personalized solutions in the past 7 days.

    Join the community of 500,000 technology professionals and ask your questions.

    Join & Ask a Question

    Need Help in Real-Time?

    Connect with top rated Experts

    16 Experts available now in Live!

    Get 1:1 Help Now