Supported Hardware RAID for Installation

[jsingleton71]

Hello,

I'm struggling with my AMD board and its onboard RAID. Using the dmraid= or mdadm= option did not work, each time I boot, the installer only see's the individual drives.

So I bought a Rocket Raid 2720SGL in hopes of being able to install Debian from scratch, but it too only shows the individual drives during the installer.

Questions;

Are there any SATA RAID cards that the Debian installer will see the RAID during installation?

Are there any tutorials on how to create a custom ISO that I can include the Rocket Raid driver and then install?

Thanks,
Jeff

[steve_v]

Not that it really answers the question at hand (I have never used a hardware RAID card and probably never will), but I have to ask: Why?
Mdraid is far more flexible and is supported out of the box. For mdraid, seeing individual drives is exactly what you want.
What benefit does a hardware/firmware raid card confer that you actually need? Neither of the cards you mention have a BBWC or any other features that Linux software RAID lacks, and will only serve to tie your array to a specific piece of hardware. The performance advantages of a cheap hardware raid card vs. softraid on a modern CPU are questionable at best, and I have seen more than one that are actually slower.

If you're going for a raid card because you're coming from Windoze (and Windoze softraid sucks hard), forget all that. Linux mdraid is excellent.

If you really do need 3rd party drivers for the install, and you have them compiled for the kernel the installer is using, you should be able to load the .ko from a USB drive by dropping to a shell prior to running the installer. Remember to ensure it is also copied to the installed system and included in the initrd when installation is done. If you want to boot from such an array it will also need to be supported (and loaded) by GRUB.
If all you have is the driver source you will first need to compile it on the livecd or another Debian machine with the same kernel.

Really, mdraid is far easier to set up - and you can run your array on any machine that has enough ports.

As for building a custom install cd, yes, there are many tutorials on the www, and there's more than one way to do it. For a single use though, it's probably easier to just load the driver from a USB disk.

[jsingleton71]

Thank-you for the response.

I really didn't realize how powerful mdraid was. But for whatever reason that still doesn't work with my AMD board's chipset. Hence why I tried to get a hardware raid card that has Linux support. I suppose I could try to mdadm= at boot time while using the hardware card as my controller. Maybe that will work.

I'm a long time Linux user and have built a new system and wanted to go big or go home. That is why I am here asking these questions. I guess now that I have spent the money on the hardware card I would like to use it, so that should explain the why.

[jsingleton71]

Well...

Neither dmraid= nor mdadm= is working for me. Each time I get to the second phase of the installation, i.e. booting to rescue mode to install grub, it never see's the /dev/dm* or /dev/md* raid.

I tried simple-cdd and that doesn't work either since it doesn't build the ISO based on my system, it downloads everything.

I need to be able to include a custom ko kernel module into the default debian installer.
Is that possible?

[steve_v]

Each time I get to the second phase of the installation, i.e. booting to rescue mode to install grub, it never see's the /dev/dm* or /dev/md* raid.

GRUB shouldn't (and can't AFAIK) be installed to an md device, but rather each of the component drives.

My preferred option would be to disable all raid functions (card BIOS?) and let mdraid use the raw disks, ala IT mode. It's been a long time since I used the installer (installs tend to get upgraded / moved to new hardware instead), but IIRC if it can see the individual disks, they should be available to create a RAID from the installer. Is it the initial mdraid setup or trying to boot from it that's causing issues?
Does mdadm --assemble --scan find your array?

I need to be able to include a custom ko kernel module into the default debian installer.
Is that possible?

Well, if you have a compiled .ko for the correct kernel version, just put it somewhere you can find and load it from a shell. Adding it to the iso (usual iso rebuilding tools etc.) or putting it on a removable (USB/floppy/CD etc.) disk should work. Incorporating it fully into the installer (with autodetection etc.) is likely possible, but beyond my debian-foo right now.

A quick look at the *buntu page for these cards suggests that you will have to compile the driver, and that looks to be a bit of a pain... But I don't have one to play with (running LSI SAS 2008 in IT mode here) so I'm not sure how much help I can offer.

That the installer sees the individual disks tends to suggest that it already has a driver though...
Maybe someone else here actually has one of these cards to muck about with.

[jsingleton71]

Thanks Steve

For some reason it may be just my misreading the directions. So I am trying again with dmraid=true option at boot.

In the Advanced section of the boot menu, I select Rescue Mode, and edit + add the dmraid=true again. When it asks which partition to mount as root, the RAID is not listed, but the option to configure the RAID is (weird). I have tried that option and it fails to mount /dev/md0 which is the RAID, but not the root partition...the root partition is not listed nor is any other partition on the RAID.

I did install Debian to a single raw disk and successfully compiled the driver, but my dumbass forgot to scp it off for safe keeping. I will probably try this again should this next try not work.

All I want is to Stripe my disks, then partition them and install Debian. That doesn't sound to hard...right? LOL.

EDIT

Nope...I definitely am doing this right, but for some reason the installer just will not see the md RAID nor the dm RAID or any RAID at all.

The really aggravating part is that the installer see's the RAID no matter if I use dmraid=true or mdadm=true or not.
What a waste of hardware this will be if I can't boot a RAID with Debian.

[acewiza]

I recently also went through some RAID-based headaches. Not exactly what you are experiencing, but I went through several different controllers, install attempts and fruitless searching before deciding to try this:

https://www.howtoforge.com/software-raid1-grub-boot-debian-etch

I know etch is old, but the procedure looks viable.