Power Log Collector: Difference between revisions

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(no, it doesn't use powerd at all, it only collects logs.)
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'''Note''': will not work on secured laptops without signing.
'''Note''': will not work on secured laptops without signing.


Does not work for XO-1.75 yet.
Logs the actions of [http://dev.laptop.org/git/users/pgf/powerd/tree/powerd powerd], using the [http://dev.laptop.org/git/users/pgf/powerd/tree/olpc-pwr-log.sh pwr-log.sh script].


= How to Use =


= Use =
* Download [[media:Power-log-collector.tar.bz2|Power-log-collector.tar.bz2]] and unpack onto a USB flash drive,
* Download [[media:Power-log-collector.tar.bz2|Power-log-collector.tar.bz2]] and unpack onto a USB flash drive,
* Shut down the XO,
* [[Shutdown|Shut down]] the XO,
* Insert the USB drive, and
* Insert the USB drive, and
* Turn on the XO.
* Turn on the XO.


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


= Theory of Operation =
= Theory of Operation =
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* executes rc.local on that drive, which does the collection.
* executes rc.local on that drive, which does the collection.


= Modifying Tiny Core Linux =
= How it was Made =

This will unpack the initial ramdisk to the current directory.
It was made by remastering Tiny Core Linux.

Unpack the initial ramdisk to the current directory:
# gunzip <../initrd.gz | cpio -i
# gunzip <../initrd.gz | cpio -i

# Modify as needed
Modify the files as needed, then repack the initial ramdisk:
# find | sudo cpio -o -H newc --quiet | gzip -2 > ../initrd.gz
# find | sudo cpio -o -H newc --quiet | gzip -2 > ../initrd.gz


Then assemble into a .tar.bz2 for download.
= rc.local =
= rc.local =



Revision as of 22:26, 18 November 2011

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