LEX NEO – A fanless CF-Boot Setup

This tutorial tries to show you how to setup a wonderful quiet fanless system.
I’ve bought a LEX NEO, a terribly nice Mini-ITX fanless barebone which includes an onboard bootable CF-card slot.
Thomas Bocek (nope.ch) helped me out with the following configuration.
The idea was:

The harddisk should only run when used
The whole system should be stored on a CF-card
We don’t want to stress our CF-card. Directories with a lot of access like /var/log should be run in RAM

We decided to install Debian Linux by USB-install, using a USB-stick instead of running some PXE network install which seems to be far more complicated.
Here’s a short HOWTO (for more detailed instructions, please check Debian USB memory stick booting:
Download boot.img.gz (7.9 MB). Also, download the official netinst image (108 MB). If you can’t find it, check http://www.debian.org/CD/netinst/ and download the stable i386 version.

Now, prepare the USB-stick:


$> dd if=boot.img of=/dev/sda
$> mount -t vfat /dev/sda /mnt/
$> cp debian-31r0a-i386-netinst.iso /mnt/

$> dd if=boot.img of=/dev/sda

$> mount -t vfat /dev/sda /mnt/

$> cp debian-31r0a-i386-netinst.iso /mnt/

Boot from your USB-stick and install Debian Linux on your CF-card. If it won’t recognize your CF-card, you might want to disable DMA („ide=nodma“ as boot parameter). My CF-card, a SanDisk Ultra II 1GB, did not support DMA.

As soon as your system is set up, configure it to run directories with a lot of write-access completely in RAM.
Let’s create /sbin/preinit:


#!/bin/bash

echo "creating tmpfs in /var/log"
mount -n -t tmpfs tmpfs /var/log
echo "copy /var/log"
cp -a /var/log_persistent/* /var/log
echo "set dma on for hdd"
hdparm -d1 /dev/hdd
hdparm -B0 -S18 /dev/hdd
echo "done, resume normal operations..."
exec /sbin/init

#!/bin/bash

echo "creating tmpfs in /var/log"

mount -n -t tmpfs tmpfs /var/log

echo "copy /var/log"

cp -a /var/log_persistent/* /var/log

echo "set dma on for hdd"

hdparm -d1 /dev/hdd

hdparm -B0 -S18 /dev/hdd

echo "done, resume normal operations..."

exec /sbin/init

This will copy all data from /var/log_persistant to /var/log which is located in RAM as tmpfs on boot-up. Also, it sets the harddrive’s APM to extremely aggressive (-B0) and standby/spindown timeout to 1:30 minutes (-S18).
Make sure, this runs before the default init.d scripts. We managed this by specifying the init parameter in GRUB, /boot/grub/menu.lst:


title           Debian GNU/Linux, kernel 2.6.8-2-386
root            (hd0,0)
kernel          /boot/vmlinuz-2.6.8-2-386 root=/dev/hdc1 ro init=/sbin/preinit ide=nodma
initrd          /boot/initrd.img-2.6.8-2-386
savedefault
boot

title Debian GNU/Linux, kernel 2.6.8-2-386

root (hd0,0)

kernel /boot/vmlinuz-2.6.8-2-386 root=/dev/hdc1 ro init=/sbin/preinit ide=nodma

initrd /boot/initrd.img-2.6.8-2-386

savedefault

boot

Next, set up /etc/fstab:


proc            /proc           proc    defaults        0       0
/dev/hdc1       /               ext2    defaults,errors=remount-ro 0       1
/dev/hdd1       /myharddisk     ext3    defaults,errors=remount-ro 0       1
tmpfs           /var/run        tmpfs   defaults        0       0
tmpfs           /var/lock       tmpfs   defaults        0       0
tmpfs           /var/log        tmpfs   defaults        0       0
tmpfs           /tmp            tmpfs   defaults        0       0

proc /proc proc defaults 0 0

/dev/hdc1 / ext2 defaults,errors=remount-ro 0 1

/dev/hdd1 /myharddisk ext3 defaults,errors=remount-ro 0 1

tmpfs /var/run tmpfs defaults 0 0

tmpfs /var/lock tmpfs defaults 0 0

tmpfs /var/log tmpfs defaults 0 0

tmpfs /tmp tmpfs defaults 0 0

/dev/hdc represents the CF-card on Secondary Master, /dev/hdd is the harddisk on Secondary Slave.

As you see, we’re now running the following directories in RAM:
/var/log, /var/run, /var/lock, /var/log, /tmp
All we need to do now, is synchronizing back the /var/log data to our CF-card every hour and on a shutdown
/etc/cron.hourly/backup-var:


#!/bin/bash
rsync -ax --delete --temp-dir=/tmp /var/log/* /var/log_persistent

#!/bin/bash

rsync -ax --delete --temp-dir=/tmp /var/log/* /var/log_persistent

Create /etc/init.d/commit:


#!/bin/sh

case "$1" in
start)  echo -n "n/a"
echo "."
;;
stop)   echo -n "Comitting changes and backup"
/etc/cron.hourly/backup-var
echo "."
;;
restart) echo -n "n/a"
echo "."
;;
reload|force-reload) echo -n "n/a"
echo "."
;;
*)      echo "Usage: /etc/init.d/commit start|stop|restart|reload|force-reload"
exit 1
;;
esac
exit 0

#!/bin/sh

case "$1" in

start) echo -n "n/a"

echo "."

;;

stop) echo -n "Comitting changes and backup"

/etc/cron.hourly/backup-var

echo "."

;;

restart) echo -n "n/a"

echo "."

;;

reload|force-reload) echo -n "n/a"

echo "."

;;

*) echo "Usage: /etc/init.d/commit start|stop|restart|reload|force-reload"

exit 1

;;

esac

exit 0

Add the commit script to all necessary runlevels:


$> cd /etc/init.d
$> update-rc.d commit defaults

$> cd /etc/init.d

$> update-rc.d commit defaults

That’s it! Enjoy your slick silent baby!

5 Responses

Marc
Jun 28, 2007 - 05:19 PM

Hello,

Note that with debian etch, you can install the flashybrid package which automatically does more or less the same thing.

Marc
Henrique Brancher Gravina
Jan 12, 2008 - 03:18 AM

Nice! this instructions works very well to me. Ubuntu Server 7.10, Thanks.

Only the chmod +x commands are not in the text.
Thomas Verchow
Feb 27, 2008 - 12:02 AM

Add the mount option „noatime“ to your grub/menu.lst to avoid updating the access time. This is something you really want to do 🙂

Regards!
Ppaul
Dez 17, 2008 - 10:38 PM

I am trying to install Monowall or Pfsense firewall on a Lex Light PC but it does not have CF card, I have only one 20GB HDD.

How can I do it? Because the disk is on Secondary Mater.