Joachim Breitner

Silencing my Slug

Published 2006-03-12 in sections English, Digital World.

Some time ago, I bought a LinkSys NSLU2, that's a very cute little box with power, usb and network plugs, and nothing more. Inside sits an ARM processor and 16MB RAM. The great thing is: You can install linux on it, even a complete Debian sarge installation.

The box is not very performant, even after I de-underclocked it by scraping away a resistor from 133MHz to 266Mhz, but it is quite cheap and very handy. I use it for nightly backups. Unfortunately, the attached external Maxtor OneTouch harddrive is quite loud, even when it is idle. Here are the steps I took to make the setup zero-noise as long as the slug is doing nothing:

  • Set the spin down time for the hard drive using sdparm.
  • Use noatime on all mounted disks.
  • Use ext2, not ext3. (maybe that is not necessary, I'll try with ext3 some time)
  • Run syslogd with "-m 0" to get rid of the 20-minutes "--MARK--" entries. (For debian, set it in /etc/init.d/sysklogd)
  • Of course, only run stuff you actually need
  • And the final step, just figured out: Mount /var/run on a tmpfs. Daemons like openvpn seem to write there on regular intervals, so keep these away from the hard drive.

Some further plans for my slug involve a USB attached LCD display and a temperature sensor, so I can be informed about various stuff, incuding the outside temperature, even with my regular computer off. Suggestions of what hardware I could use is highly appreciated.

Comments

How about getting the NSLU2 to retreive via the HTTP the weather forecast from the your local weather bureau, and then display a summary of that on your LCD? Then you could have the current weather outside, plus the forecast, without turning your regular computer on.
#1 NJ (Homepage) am 2006-04-24
Sounds good, although I have not gotten around to get a LCD display.
#2 Joachim Breitner (Homepage) am 2006-04-24
Hi,

you may have a look about how to run a USB- (or Ethernet-)Display on your NSLU (or on a Fritzbox DSL-Router, alternatively) here (in German):
http://www.nslu2-info.de/showthread.php?t=4434

Very nice displays (and also the software to configure them) can be found in this great support-forum from rage:
http://www.ct-maeusekino.de

Kind regards,
ao

PS: Could you please give me some details (for a Linux-Newbie) on sdparm, the noatime setting (where/how to put it), sylogd and tmpfs?

I do not understand how to use Andreas' Skript (http://www.nslu2-linux.org/wiki/HowTo/SetSpinDownTimeOnMaxtorOneTouch) on Unslung 6.8.
#3 agent orange (Homepage) am 2006-09-01
Thanks for the links. Currently, my SLUG is doing its work in a different climate zone, but when I'm back I'll look into it.

For the silencing, I don't remember much, it has been some time. "noatime" is an option to set in the fstab, and that's where you mount stuff with tmpfs:

none /var/run tmpfs defaults,size=512K 0 0
#4 Joachim Breitner (Homepage) am 2006-09-03
just wanted to note that it's better to set the syslogd -m 0 parameter in /etc/default/syslogd..
#5 bakotaco (Homepage) am 2007-05-27
True, unless you are running sarge, in which case this file does not exist yet.

Thanks for the hint!
#6 Joachim Breitner (Homepage) am 2007-05-28
thanks for your info
When I add the tmpfs line into fstab, will I see this if I type 'mount' as root?
Just to be sure...
(I don't see it, and guess this is not good!)
thanks
vincent
#7 vincent am 2007-08-01
It should:

# mount
/dev/sda3 on / type ext3 (rw,noatime)
proc on /proc type proc (rw)
sysfs on /sys type sysfs (rw)
devpts on /dev/pts type devpts (rw,gid=5,mode=620)
tmpfs on /dev/shm type tmpfs (rw)
usbfs on /proc/bus/usb type usbfs (rw)
none on /dev/shm type tmpfs (rw)
none on /var/run type tmpfs (rw,size=512K)
/dev/sda4 on /bigmedia type ext3 (rw,noatime)
/dev/sda1 on /backup/image1 type ext3 (rw,noatime)
/dev/sda6 on /backup/image2 type ext3 (rw,noatime)

Did you restart?
#8 Joachim Breitner (Homepage) am 2007-08-02

Have something to say? You can post a comment by sending an e-Mail to me at <mail@joachim-breitner.de>, and I will include it here.