AHCI Raid clean install

I just got a couple new hard drives and would like to do a clean install in a raid 1 (mirror) configuration. My motherboard is an ECS GF8200A which has an Nvidia 8200 chip which supports AHCI raid in the bios.

From what I understand, AHCI is a “fakeraid” setup, so my question is what do I need to do during install (if anything) to make sure SUSE detects it and installs correctly?

I read the OpenSUSE software raid guide, but I wasn’t sure if it pertained to AHCI since it’s a sort of “blend” of pure software and hardware raid.

Shameless bump :slight_smile:

If I’ve butchered my question to the point that nobody knows what I’m talking about, please let me know and I’ll try to rephrase/reformat it.

You have a few options. The “Soft” raid you are doing should be transparent to the OS if done correctly. However, you can also do RAID right from within Linux that won’t rely on any external devices (other than your hard drives) so you can move the entire setup to another machine that does not have the same controller

Thank you for the reply. I would consider disabling the “RAID” feature in the motherboard BIOS and using OPENSUSE to set up a software RAID instead (with a RAID 1 it probably won’t affect the speed either way), except this motherboard won’t let you use some of the SATA slots unless they’re used in a RAID.

(It’s a weird motherboard, but it’s what I have to work with.)

I guess what I’m asking is whether or not I’ll have to set anything up in the OpenSUSE install to specifically detect the RAID if it’s preconfigured in the BIOS. It would seem like the BIOS RAID controller would only let OpenSUSE see one drive for my mirror configuration, but from what little information I’ve found it seems that AHCI RAID needs support from the OS in order to work properly even if the BIOS is set up already.

I know I’m putting the cart before the horse a bit and should just try it out and see what happens, but I’m trying to limit the time the system is down while I upgrade, and don’t want to get the install complete only to find out that I’ve configured it wrong down the road and one of the disks isn’t being utilized…

Are you sure about the “not using the sata ports” unless it is in RAID or just that it must be on the “RAID controller” but can exist as JBOD? what is the make/model. I am interested now.

Don’t know (sorry). The motherboard is an ECS GF8200A. In the manual (downloadable here) it says that SATA ports 4 and 5 are only accessible in a raid configuration. On some other forums for this motherboard, people were complaining that they can’t use SATA port 4 and 5, but none of them were using a RAID or JBOD setup as far as I know.

From looking at the BIOS screen shots, it appears that there are 3 modes for the SATA port controller, SATA, AHCI and RAID. My guess is that you can enable the mode as RAID and continue to use the ports without defining an array. If that is the case, I don’t know what implications this will have on bootup, but you should not have to define an array, hopefully to use all 5 ports. Alternately, you could look at a SATA card, as they run about $20 US.

Cool. If it does end up taking any special configuration I’ll post here with the results.

Thanks again!

In case anyone else has this weird MB and wants to use all SATA ports:

AHCI enabled in the BIOS made it so all 5 SATA ports work (the RAID setting was not required). SUSE detected it just fine without any additional configuration, and I was able to define a software raid without trouble.

Thank you.

I have set up a raid 1 with mdadm. The disks run in AHCI mode. The raid sometimes logs errors of type “access beyond end of device” to /var/log/messages. I have done a fsck.ext3 and it found errors. I hope that this ended the erroneous situation and it will be stable now. Time will tell.

I do not have the slightest idea on what caused the errors in the first place. Maybe it had to do with accessing the raid before the initial resync was done. Although the resync is a background process which should not prevent usage of the raid.

I would really appreciate input on that issue because it did not strengthen my confidence in the safety of my valuable data…

The sync is really just a file copy on RAID 1. The errors could be with the disk, an unclean shutdown or other file system issue

If you have smartd enabled, run smartctl -a against all your disk devices and check for any errors.