[CentOS] RAID5 or RAID50 for database?

[Linux]

On Fri, May 23, 2008 at 4:19 AM, Christopher Chan
<christopher at ias.com.hk> wrote:
>
>> And stick with md-raid 10 (also known as software raid) because it is
>> much more intelligently designed than any
>> closed-source-embedded-raid-controller.
>
> This was valid until...quite a few years ago.

Has hardware-raid vendors open-sourced their firmware then?

>> Nowadays hardware raid frightens me because of the need to have spare
>> raid-controllers for every hardware-raid-configuration I have. They
>> are neither interchangable nor easily recoverable.
>
> You seem to have been living under a rock for the last half decade.

For each hardware-raid configuration I keep a redundant
raid-controller. In case of controller failure it's the best way to
recover my data on disks. I tried simple test cases once (yes, on the
last half decade) and most failed except simple RAID-1 configurations.

>> md-raid 10 can be established with any number of disks (at least 3 but
>> better check with google)
>
> Hmm, I think your advice must be taken with a grain of salt. Have you
> actually tried to do what you suggest? In any case, I will give you the
> benefit of the doubt that you just did a typo.

mdadm raid10 is neither raid 1+0 nor raid 0+1. Go check with man mdadm
or google. Each stripe is written on 2 different disks with a rolling
frame and loss of 1 disk in 3 disk configuration can be recovered
online.