[CentOS] RAID5 or RAID50 for database?

> 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.

> 
> 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.

> 
> 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.