When I was said, “Unable to boot”

Table of Contents

I tried to install Lubuntu into really old machine, Let’s Note CF-W2. Then I got the following message.

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

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This kernel requires the following features not present on the CPU:
pae

Unable to boot - please use a kernel appropriate for your CPU.

Let’s Note CF-W2 のスペックは次の通りです。

Environment

Specification

CPU: Intel Pemtium M 32bit 1GHz
RAM: 1GB

OS Image (ISO)

lubuntu-14.04.3-desktop-i386.iso

Reason

The message seems to imply “You are installing 64 bit image into 32 bit machine”, but it’s not correct.

The exact reason is that Intel Pentium M doesn’t support PAE.

PAE

Technology to enable 32 bit CPU to handle memory more than 4 GB. It is implemented not only by Intel, also by AMD.

Solution

私がとった解決策は次の方法です。 Ubuntu の forcepae オプションを使います。

Boot Lubuntu from DVD.
Select language.
Press F6 key and ESC key.
Then you can see the command like the following.

Boot Options file=/cdrom/preseed/ubuntu.seed boot=casper initrd=/casper/initrd.lz quiet splash --

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Boot Options file=/cdrom/preseed/ubuntu.seed boot=casper initrd=/casper/initrd.lz quiet splash --
Now select “Install” by up or down key.
Then change the command displayed, like the following. Put “forcepae” into 2 places.

Boot Options file=/cdrom/preseed/ubuntu.seed boot=casper initrd=/casper/initrd.lz quiet splash forcepae -- forcepae

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Boot Options file=/cdrom/preseed/ubuntu.seed boot=casper initrd=/casper/initrd.lz quiet splash forcepae -- forcepae
- The first one is an option for kernel booted for installation, and the second one is an option for kernel to be installed.