Power Log Collector

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Revision as of 22:26, 18 November 2011 by Quozl (talk | contribs) (no, it doesn't use powerd at all, it only collects logs.)
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This Power Log Collector boots an XO-1 or XO-1.5 and copies the power logs to itself before shutting the laptop down.

Note: will not work on secured laptops without signing.

Does not work for XO-1.75 yet.

How to Use

The XO will collect the power logs, print a message saying has done so and then shut down.

Theory of Operation

  • Based on Tiny Core Linux,
  • An Open Firmware Boot Script selects the XO-1 or XO-1.5 kernel,
  • The initial ramdisk mounts /dev/sda (which should be the first USB drive), and
  • executes rc.local on that drive, which does the collection.

How it was Made

It was made by remastering Tiny Core Linux.

Unpack the initial ramdisk to the current directory:

  1. gunzip <../initrd.gz | cpio -i

Modify the files as needed, then repack the initial ramdisk:

  1. find | sudo cpio -o -H newc --quiet | gzip -2 > ../initrd.gz

Then assemble into a .tar.bz2 for download.

rc.local

The script that does the collection:

#!/bin/sh

uname -a | grep _xo1-
if [ $? -eq 0 ]
then
       echo detected xo-1.0
       XO_ROOT=mtdblock0
       XO_FS=jffs2
else
       echo detected xo-1.5
       XO_ROOT=mmcblk0p2
       XO_FS=ext3
fi

mkdir -p /mnt/$XO_ROOT

mount -t $XO_FS -o ro /dev/$XO_ROOT /mnt/$XO_ROOT
mkdir -p /mnt/sda1/power-logs
cp /mnt/$XO_ROOT/home/olpc/power-logs/* /mnt/sda1/power-logs
umount /mnt/$XO_ROOT
mount /dev/sda1 /mnt/sda1 -o remount,ro
sync
echo Power Logs Recovered
echo Shutting down in 10 seconds
echo You may remove the USB now
sleep 10
poweroff