fedora 17 cant see my raid 5 disk array

[kubiej21]

Hello everyone, this is my first post, so if Iam in the wrong section, Iapologize.

I setup a home server running fedora 17 and it doesn't seem to be able to see my hard drives that are setup in raid 5. The os installed just fine on a non raid hdd. During th installation process, Inoticed that it threw a warning about bios metadata and reading sde, sdc, or something along those lines (Ididnt pay too close attention to it). The motherboard Iam using is a biostar A870U3. I took a look on biostar's website, but couldn't locate any drivers for the board. Any suggestions as to what Ican do?

[george_toolan]

What kind of RAID is this?

Linux software RAID or fakeraid with the AMD 870/SB850 chipset?

How did you create the RAID?

[droidhacker]

From the error about "bios" raid, he's using fakeraid for sure.

kubiej21: You've made the terrifying mistake of setting up a pretend raid5 array. In fact, your "raid" card is nothing besides a typical non-raid sata controller. All raid function is implemented in the DRIVER, and not actually within the raid card.

What this means is that you will experience dismal performance out of your array.

There are three kinds of raid;
Hardware RAID,
Software RAID,
and FAKE RAID.

Fake raid is software raid that PRETENDS to be hardware raid.

Hardware raid has the PERFORMANCE advantage, CROSS PLATFORM advantage, and portability DISADVANTAGE.
Software raid has the PORTABILITY advantage (it isn't tied to the controller), cross platform DISADVANTAGE, and performance DISADVANTAGE.

Fakeraid has the PERFORMANCE DISADVANTAGE, CROSS PLATFORM DISADVANTAGE, and the PORTABILITY DISADVANTAGE. There is NO advantage at all. It is slow, and it is tied to the controller.

My recommendation is to back up that data and build a software array. If the array needs to be accessed by multiple non-cooperative operating systems, either pick up a genuine RAID card, or you may consider using fakeraid in a MIRRORING arrangement. DMRAID is typically able to handle fakeraid mirrors, but raid5 is a bit much since it depends on specific implementation details.


Note that fakeraid came about as a sales-feature for budget low-end cards. Junk like the promise fasttrak card which would sell for about $50.
A real raid card will have a much higher starting price. Used to start at around $500+ for a 4-port raid card. Now you can start to see entry level LSI cards for around $250.

[kubiej21]

Fakeraid... That definitely must be my issue... Looks like I'll be doing some hardware upgrades.

Thanks for the info!