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I just installed Debian onto an SD card via my laptop. I have now moved that SD card to my server and tried to boot from it. The error it's giving me is:

This kernel requires the following features not present on this CPU:
Unable to boot - please use a kernel appropriate for this CPU.

Is this Debian install doomed? Do I have to start over? Or is it possible to install a new kernel on this unbootable OS?

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LiveCD + New Kernel files = Fixed OS – Chris S Dec 14 '10 at 5:20
For realz? How do I install the new kernel to the hard drive? I assume a package-manager is out as that will install the kernel for the LiveCD and not my SD card... Do I have to manually compile and set the paths? – micsd Dec 14 '10 at 5:23

The usual way is:

  • boot from a LiveCD or LiveUSB
  • mount filesystems of the broken OS (as a minimum, you need / and /boot from there) — suppose that they are mounted in /mnt/tmp
  • mount special filesystems:
    • mount --bind /dev /mnt/tmp/dev
    • mount --bind /proc /mnt/tmp/proc
    • mount --bind /sys /mnt/tmp/sys
  • chroot /mnt/tmp
  • now install whatever packages you need, change other configuration; network will be accessible as set up in the LiveCD environment
  • exit to leave chroot
  • unmount filesystems

In simple cases you may not need the full chroot procedure; package installation, however, most likely needs one (and scripts, especially in kernel-related packages, may need /dev, /proc and /sys).

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