Linux Networking Software

CIFS: mount error(13): Permission denied

You’ve just updated your Raspberry Pi (or whatever Linux) and you’re noticing your CIFS (smb) mounts aren’t getting auto mounted anymore. You curse and start noticing this error:

# mount -t cifs // -o username=public,password=public sam/
mount error(13): Permission denied
Refer to the mount.cifs(8) manual page (e.g. man mount.cifs)

The solution is to add after -o username=X,password=Y the following: sec=ntlm; thus it becomes -o username=X,password=Y,sec=ntlm.

You can do the same in fstab:

// /mnt/sam/ cifs domain=TIETE,username=public,password=public,sec=ntlm 0 0

No idea why it’s suddenly required, but whatevs.

Hardware Linux Networking Software

Raspberry Pi & @Flightradar24

In a couple of lines: how to get FR24 (+ dump1090) to work on your Raspberry Pi.

Be sure to have the right hardware: and … obviously … a RPi.

I got a NooElec from Amazon because I didn’t have the patience to wait for something (that might not work) from AliExpress.

As root:

apt-get update && apt-get install cmake gcc pkg-config libusb-1.0 make git-core libc-dev
git clone git://
cd rtl-sdr
mkdir build
cd build
make && make install
cd ../..

And be sure to Blacklist the normal driver:

echo "blacklist dvb_usb_rtl28xxu" > /etc/modprobe.d/dvb-t.conf

And at this point you should reboot.

As regular user (screen part is no longer needed as the new FR24 program will automatically launch and execute it for you):

git clone
cd dump1090
ln -s dump1090 /bin/
screen -dmS dump ./dump1090 --interactive --net --net-beast --net-ro-port 31001 --net-http-port 8888
cd ..

Now get the FR24 software. In case you get a 404, get the latest version here new Raspberry Pi version is here, Linux (AMD64 & ARMv7) is here.
You can get your long & lat here.
Follow the updated howto on the page. The underlying code is no longer relevant.

tar xvzf fr24feed*
./fr24feed_arm-rpi_242 --signup

I’ll ask a couple of questions (answer them correctly):

Step 1/5 - Enter Latitude (DD.DDDD)
Step 2/5 - Enter Longitude (DD.DDDD)
Step 3/5 - Enter your email address ([email protected])
$:[email protected]
Step 4/5 - Enter your the hostname of the data feed (leave empty for localhost)
Step 5/5 - Enter your the port number of the data feed (leave empty for 30003)

Validating form data...OK

The closest airport found is 'Brussels Airport (ICAO:EBBR IATA:BRU)' near Brussels.

Latitude: 50.901379
Longitude: 4.484444
Country: Belgium

Flightradar24 may, if needed, use your email address to contact you regarding your data feed.

Would you like to continue using these settings?



It will give you a key (and e-mail it to you) after a couple of minutes. Keep this key, as it’s important.

That’s it. As dump1090 is already running, all you have to do is start flightradar and you’re good to go.

This is the script I use to start it all (in screen, allowing me to check it). As normal user:

nano -w

And copy paste the following (+ edit the variables):


pro script

cd $DIR

Start dump1090

cd dump1090

I run on port 8888 because 8080 is taken on my rasp


#screen -dmS dump ./dump1090 --interactive --net --net-beast --net-ro-port 31001 --net-http-port 8888
cd ..

Start Flightradar24

screen -dmS flightradar24 ./fr24feed_arm-rpi_242 --fr24key=$KEY

And run: chmod +x

To start the script, simply run ./, and check what’s happening with screen -r dump or screen -r flightradar.

To auto start this script at boot time, I edit rc.local as root:

nano -w /etc/rc.local

And add the following at the end but BEFORE exit 0:

su yeri -c /home/yeri/

Obviously, modify the path and the user it should run under (in this case as “yeri”).

PS: Be sure to signup again every time you move your Raspberry around (the coords seem to be hardcoded in the key).
PPS: You can get Premium access here now: (and check fancy graphs about your “radar”).

Hardware Linux

Yard Sale: Raspberry Pi’s

Today I’m selling Raspberry Pi’s.


4 are unused, new, in packaging. I have a couple more (about 6) who got used for a couple of hours, but never anything serious.

I am also selling the power adapter and the laser cut casing.

 IMG_20140417_172914_2 IMG_20140417_172909_2

Raspberry Pi: €30,49/item (type B – 512 Mb RAM)

PSU: €4.45/item

Casing: €4/item

Possible on invoice.

Contact: [email protected]

Hardware Linux Software

Munin + Raspberry Pi + temperature: updated

I got a mail in my inbox about a week ago from Anthony, telling me how to improve my Munin & temp script for a RPi:


I just read your (old) blog post about monitoring the temperature of the Raspberry Pi with munin[1].

I had the exact same error as you did when I was trying to let munin do the job all by himself:

> temp.value VCHI initialization failed)

It turns out the solution was quite easy: in


You simply need to tell munin that it needs to run as root for this specific plugin:

> [pisense_]

> user root

(the plugins also tracks clock speeds and voltages but any other will work just fine as long as the “user root” is set in the munin-node plugin config file : [2]). Probably the easiest way to check if it’s working is to use munin-run command before and after the change.

“Demo”: [3]

By the way, “Connect different LANs over openVPN” is pretty tempting, I always wondered what the performances would be like through a USB-to-ethernet adapter.

Have a nice one !



And indeed, I knew it was a permission issue, but instead of running this script as root, I tried adding Munin to a group that was supposed to be able to run  vcgencmd (which didn’t work out).

But, let’s look at a simpler solution:

  1. Go to /etc/munin/plugins and create a file temp with this content (and some indentation yourself):
    case $1 in
    cat <<'EOM'
    graph_category system
    graph_title Temperature
    graph_vlabel temp
    temp.label Celsius
    exit 0;;
    echo -n "temp.value "
    /opt/vc/bin/vcgencmd measure_temp | cut -d "=" -f2 | cut -d "'" -f1
  2. As you noticed, this doesn’t require any more scripts to run from cron (and thus, in case you used my previous script, remove it from cron)
  3. chmod +x temp
  4. Make sure it runs as root; in /etc/munin/plugin-conf.d create the file temp.conf with this content:
    user root
  5. Test it:
    # munin-run temp
    temp.value 59.5

Tadaaaa. Simpler.

Thanks Anthony 🙂


Why historical data matters (and is just cool to look at)

CPU temperature from a Raspberry Pi (behind the display, in the wall).

temp(zoom in)