Boot after kernel recompile

[James Wilkinson]

Juan L. Pastor wrote:
> The kernel that comes with my Fedora Core 2 is 2.6.5-1.358. I have
> recompiled and installed kernel 2.6.6-1.435.2.3. The problem is that
> after make mrproper, make xconfig, sudo make modules_install install and
> editing /etc/grub.conf so that I restart with the new kernel, I get a
> kernel panic. 
> 
<snip>
> 
> I have changed the root=LABEL=/ parameter of the first entry by
> root=/dev/hdc2 and the problem has disappeared. My question is why it
> works for the default installation and not after having recompiled a new
> kernel.

Yup. It does that.

The Fedora kernels have an initrd, a RAM disk that gets mounted as a
root filesystem early in the boot process. This contains the modules
needed for the system to boot [1], and the mount command that can mount
filesystems by label [2]. This means that with the Fedora kernels,
specifying the real root filesystem is done with userspace tools.

Without an initrd, the kernel mounts the root filesystem itself. It
doesn't know about ext3 labels.

You can either investigate mkinitrd, or carry on the way you're doing
things.

HTH,

James.

[1] If you've compiled the kernel yourself, and it's booting, you've
probably compiled these into the kernel itself. This means you don't
*need* to have an initrd. This is what I do.

[2] And other things.

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