Linux wrote:
On Fri, May 23, 2008 at 4:19 AM, Christopher Chan christopher@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?
So? Has the vendor of your motherboard open sourced their firmware? Do you flash a piece of open source bios code into your motherboard's chip if not so?
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.
Sorry, I have never had a 3ware card fail on me during my four years at Outblaze Ltd. and besides, other users of 3ware had just have to plug in another card and they got all their data back. Of course, I have heard of horror stories with other brands like Mylex which might act up on a reboot.
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.
OH, you were talking about that new module that is not available on Centos 4. That is the problem these days, acronyms are not necessarily uniform. Sorry, no experience with that particular module and I think this should clear up a lot of misunderstanding on answering questions about how do I make a "raid10" array during installation.