Re: Linux mdadm superblock question.

From: Goswin von Brederlow
Date: Wed Feb 17 2010 - 22:40:37 EST


Gabor Gombas <gombasg@xxxxxxxxxxxx> writes:

> On Wed, Feb 17, 2010 at 02:26:46PM +0100, Frans Pop wrote:
>
>> That's simply not true, at least not for Debian. If you actually use the
>> distro tools [1] the only assumptions are made at kernel *installation*
>> time, not at kernel build time.
>
> And that's why network-booted diskless clients and virtual guests have
> all sort of useless modules loaded; the HW where the kernel package was
> installed in this case is very different from the HW where the kernel
> will run. If only there were a switch to prohibit ever looking at the
> current machine's configuration when generating the initramfs...

>From my experience you must boot up your client/guest and install the
kernel in there. Then copy the kernel and initrmafs over to the boot
server for use.

Initramfs was never designed to generate an image for another system, or
worse, for a pool of different systems. You can probably make it work on
a case by case basis but that wasn't thought of during the design phase.

Interesting idea though.

>> I've been using initramfs-tools generated initrds for years without
>> problems, and that includes "root on LVM on LUKS encrypted partition"
>> and "root on LVM on RAID" setups.
>
> I've tried a couple of times to use a Debian-built initramfs with a
> custom built kernel. The kernel worked fine without an initramfs (it had
> everything built in), but it did not boot with the initramfs.
>
> Gabor

'make-kpkg ... --initrd kernel-image' should build you your custom
kernel with all the magic required to generate a working initramfs.
If not then please do file bugs.

MfG
Goswin
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/