Could raid-enabled kernel be made available?

[Michael Hipp]

Would it be possible to make a raid-enabled kernel available so systems could be
installed with raid? It would be good to be able to put /boot and / in a raid
device. (Even putting that kernel in Universe would be ok, tho it would be nice
to be able to install into raid from the install CD).

I realize Ubuntu is mostly focused on the desktop, but server use is also
"encouraged" and "supported". And raid is critical for server use. Besides, raid
usage on high-end desktops is quite common. Thank you.

[Matt Zimmerman (mdz)]

The default kernel supports RAID, and installing onto a RAID device is supported
by the Warty installer, so you'll need to be more specific about what went wrong
for you.

[Michael Hipp (michael-hipp)]

Thank you. The installer offers a dire warning that installing /boot and /
(root) onto a raid device is not supported and it says the system will not boot
if you do so. I am also taking cues from this thread (
http://ubuntuforums.org/showthread.php?t=7293&highlight=raid+kernel )where it is
stated that a custom kernel is needed to support raid and it details
considerable machinations that were required to get /boot and / to work on raid.

Is the warning incorrect or else what am I not understanding?

(I recently switched to Ubuntu from RH/FC and I realize Ubuntu is probably not
attempting to replicate the "kitchen sink" kernels of RH, but I am convinced of
the need to put all partitions into raid for redundancy purposes.)

[Matt Zimmerman (mdz)]

(In reply to comment #2)
> Thank you. The installer offers a dire warning that installing /boot and /
> (root) onto a raid device is not supported and it says the system will not boot
> if you do so. I am also taking cues from this thread (
> http://ubuntuforums.org/showthread.php?t=7293&highlight=raid+kernel )where it is
> stated that a custom kernel is needed to support raid and it details
> considerable machinations that were required to get /boot and / to work on raid.
>
> Is the warning incorrect or else what am I not understanding?

I'll defer to Colin regarding the installer. The information about the kernel
in that thread is incorrect, though. There is no need to build a custom
kernel, and the automatic initrd building process will add the necessary modules
and commands to the initrd to initialize RAID before mounting the root filesystem.

[Colin Watson (cjwatson)]

The dire warnings about installing onto RAID1 (the only level supported for / or
/boot at the moment) were removed in partman-md 17, which we have in Ubuntu
5.04. RAID1 installations should work fine these days.

[Colin Watson (cjwatson)]

(except that you may need to tweak the bootloader configuration a bit; I've seen
grub have problems)