Best practices for the use of RAID 5 and RAID 50 on Dell EqualLogic arrays have changed

By admin, August 17, 2012 10:13

Just received the latest EQL news update this morning, two things caught my eyes.

With the release of firmware version 5.2.5
- Faster recovery from a drive failure, especially with the 7200 RPM drives
- Dell is also providing, for download, an update to hard drive firmware for selected 500GB, 1TB and 2TB SATA 7200 RPM hard drives. This new drive firmware will help to improve the overall life expectancy of the drives. Updating drive firmware takes approximately 15 minutes.

My view is still the same and I’ve heard different bad stories about those bigger 7200RPM 2TB/3TB on EQL or Powervault that they tend to fail Much more often  than SAS 10K/15K, so if your application is mission critical, I would stay away from those drives but opt for IOPS instead (ie, SAS 10K/15K)

Please be advised that the best practices for the use of RAID 5 and RAID 50 on Dell EqualLogic arrays have changed. The changes to the RAID policy best practice recommendations are being made to offer enhanced protection for your data.

  • RAID 5 is no longer recommended for any business critical information on any drive type
  • RAID 50 is no longer recommended for business critical information on Class 2 7200 RPM drives of 1TB and higher capacity.

What? It seemed to my that Dell Equallogic is implicitly saying RAID10 is the ONLY CHOICE for business critical application due to it’s superior performance and reliability, and RAID60 is the optimal choice for space concern application, but and again 7200 RPM drives bigger than 1TB is not recommended for high demanding application according to the above.

So after all, can we conclude that the Near-Line (NL) SATA or SAS based 7200 RPM drive is not a suitable candidate for mission critical application after all even with highest RAID5 protection (ie, RAID50), the answer seemed YES.

3 Responses to “Best practices for the use of RAID 5 and RAID 50 on Dell EqualLogic arrays have changed”

  1. Danny says:

    I see.

    As I only have 600GB x 8, so I change the default RAID 50 to RAID 5

  2. admin says:

    RAID10 is always my first choice as it can be easily changed to RAID50, then RAID5, then RAID60. :)

  3. Danny says:

    I Just read the e-mail from Dell today.

    What is your RAID config in your PS6000? My PS-6000XV is running RAID 5

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