Mayday Emergency Information Technology Host


Release 2


Release 2. 1

Release requirements. 1

Content. 2

Download. 2

How to reproduce this build. 2

Install SW for GPS. 3

Navigation Installation. 4

USB Memory stick. 4

Navit configuration. 5

Install CUPS for printing. 5

Bluetooth check. 6

Install putty. 6

Install minicom.. 6

Install USB to serial adapter (UtS-adapter). 6

Install Virus scanner. 9

Install a malware checker. 9

Increase the size of the SWAP file. 11

Install Meld. 11

Known issues. 12


Release requirements

1)      Raspberry Pi 3B+

2)      Edimax EW-7811UTC

3)      16 GB SD card

4)      SanDisk Ultra Fit - USB-stick - 64 GB

5)      Waterproof GlobalSat BU353S4 gps BU-353S4 Cable USB GPS Receiver USB interface G Mouse Magnetic (SiRF Star IV) 1

6)      Bluetooth speaker or Bluetooth headset

7)      USB 2.0 RS232 Serial Port Header DB9 9 PIN ADAPTER CABLE PDA for Windows XP/win7 with 94CM CABLE COM Converter Port



GPS Receiver


This release supports:

1)                  Everything from Release 1

2)                  GPS receiver

3)                  Land Navigation

4)                  Printer support

5)                  Bluetooth check

6)                  USB to RS232 adapter

7)                  Putty, Minicom

8)                  Virus scanner

9)                  Malware checker

10)              Meld (Meld is a visual diff and merge tool)



You can download the zipped image file from DOWNLOADS in the menu bar.

How to reproduce this build

Execute the steps as executed for Release-1 or download it.

Install SW for GPS

The gps receiver is compatible with gpsd.

sudo apt-get install gpsd gpsd-clients python-gps

This will install gpsd and related software.

Find out on which usb it registers:

First execute the command without the GPS connected to the USB port:

ls /dev/tty*

Now connect the GPS to the USB port and run the command again.

ls /dev/tty*


The one which is delta in the list is your GPS USB port in use.


Mine registered as: ttyUSB0. But wherever you use it do not specify it as ttyusb0.

It will not work in that case.

Now try your device with the command:

gpsmon /dev/ttyUSB0

If you see this your GPS is working:

Navigation Installation

sudo apt-get install navit

Now we want to install maps for Navit.

For maps, see:

Download the maps of your choice. And keep them, as we are going to put them on the USB memory stick a bit later (at least for now).


USB Memory stick

 A USB memory stick is added for external storage.

We have opted for the SanDisk Ultra Fit - USB-stick - 64 GB as we need to make our box waterproof and it is not allowed to stick out of our case.

We want to concentrate most of the data on there as later on we will use it also for other data.

As we do not want to be hampered by file size limitations:

So we are choosing for the NTFS file system.

Insert the USB in your PC and format it as NTFS. The volume label should be “BOACONSTRICTOR”.

Now copy the maps you downloaded on your memory stick, just under the root directory will be fine. Later on, we will put them elsewhere.


Navit configuration

We want to use the maps in our Navigation tool Navit naturally. We need to inform Navit where to find the maps. We need to alter navit.xml.

sudo cp /etc/navit/navit.xml /home/pi/.navit

sudo geany navit.xml

Do the following adaptations as in attached file (you can use Meld to seek the differences with the default file).


Now make the GPS read/writable for everybody:

sudo chmod +rw ttyUSB0.


Now make the USB GPS work every time you restart:

sudo geany /etc/default/gpsd

And make it look as:

# Settings for the gpsd init script and the hotplug wrapper.

# Start the gpsd daemon automatically at boot time

# Use USB hotplugging to add new USB devices automatically to the daemon

# Devices gpsd should collect to at boot time.
# They need to be read/writeable, either by user gpsd or the group dialout.

# Other options you want to pass to gpsd


Now reboot your system and start Navit. You should see the exact spot were you are on the map in Navit.



Install CUPS for printing

sudo apt install cups

Check if CUPS has successfully been installed

dpkg -l cups

Check if CUPS is up and running:

service cups status

Set the administrator for CUPS to administrator pi:

sudo usermod -a -G lpadmin pi


Now start your web browser and as URL give: http://localhost:631/

The management page of CUPS is now visible and you can add printers.

You will have the provide credentials when adding a printer:

User: pi

Password: raspberry


Bluetooth check

Left click on the Bluetooth icon in the menu bar.

Select from the dropdown box Add Device (ensure that your BT speaker or headset is discoverable).

In our case we have opted for 3 different BT devices:

·         PLUFY Sports Bluetooth Headset Waterproof Neckband Wireless Music Headphones with Mic Earphones. Great play time, good sound and low price. But waterproof, maybe for the some minimal rain.

·         Teamyo Waterproof IP68 Headphones wireless Bluetooth earphone earpod: IP68, but limited play time.

·         Hercules Wae outdoor 04Plus: Great sound for its price and size, long play time and waterproof!


It should appear in the list of searched devices after a while.

Then pair the specific device by selecting it and click the pair button.

Once paired it will indicate:

Paired successfully. Use the audio menu to select as output device.

Then click on the audio icon

Select your device.

Now you can use it.


Install putty

For the case a serial or SSH/Telnet client is required.

sudo apt-get install putty –y


Install minicom

For the case you need filetransfer via serial port.

sudo apt-get install minicom lsof



Install USB to serial adapter (UtS-adapter)


USB to RS232 adapter

First execute the command without the UtS-adapter connected to the USB port:

ls /dev/tty*

Now connect the UtS-adapter to the USB port and run the command again.

ls /dev/tty*

The one which is delta in the list is your USB port in use.


Mine registered as: ttyUSB0. But wherever you use it do not specify it as ttyusb0.

It will not work in that case.

Now try your device with putty.

Afbeeldingsresultaat voor how to use putty for serial connection

Type at Serial line to connect to: /dev/ttyUSB0 (in your case this might be another one).

Select 9600, 8, 1, NO, NO

Now type a character with your keyboard. With no local echo none should appear on your putty screen.

Open the connection and short circuit pins 2 and 3:


If you now type character with your keyboard the character send out via TX line is received back via the RX line and it will appear on your putty screen.

This is the evidence your serial connection is working.


Install Virus scanner

sudo apt-get install clamav

After installation create a virus vault under directory /home/pi

mkdir virus


Now run virus scanner with next command:

sudo clamscan -r --move=/home/pi/virus /home/pi

The latter directory is the directory which will be scanned. So if you want to check another directory e.g. /etc you need to type:

sudo clamscan -r --move=/home/pi/virus /etc


Next command cannot be run as freshclam is ran in a daemon

sudo freshclam

Other switches and flags can be found by typing:

man clamscan

In case you want to have it executed daily do what is explained below. But think well if you really want it. If you are in dire straits you probably do not want to be held up by a virus scan, eating away your processing power and batteries. So the choice is yours. I prefer to run it manually, by typing the command. SO THE BELOW IS NOT INCLUDED IN THE DISTRIBUTION!

cd /etc/cron.daily

sudo vi daily_virusscan

Put in the file:

clamscan -r --move=/home/pi/virus  /

save it with wq! command

Make it executable via:

sudo chmod +x daily_virusscan


Install a malware checker

As well as protecting against virusses, it is also recommended to protect against malware. rkhunter (Rootkit Hunter) is a Unix-based tool that scans for rootkits, backdoors and possible local exploits. It can be installed as follows:

sudo apt-get install rkhunter

The next few commands update the data files, install the baseline database and perform the initial run.

sudo rkhunter --update

This resulted in: invalid WEB_CMD configuration option: Relative pathname: ""/bin/false"


Fixing this in config file (/etc/rkhunter.conf) by changing





Subsequently when running the command again another error is encountered:

 rkhunter --update

[ Rootkit Hunter version 1.4.2 ]


Checking rkhunter data files...

Checking file mirrors.dat                            [ Skipped ]

Checking file programs_bad.dat               [ Update failed ]

Checking file backdoorports.dat               [ Update failed ]

Checking file suspscan.dat                         [ Update failed ]

Checking file i18n versions                         [ Update failed ]

Again do an adaptation in the file /etc/rkhunter.conf.









rkhunter --update

And now you can run for malware checking:

sudo rkhunter --check


Increase the size of the SWAP file

We noticed during the testing the swapfile is running constantly at 100%, so we increase it.

Change the size in /etc/dphys-swapfile:





Restart the system.

There is a lot of discussion on swap files located on your SD card. It is considered to be slow, it is considered to be destructive for your SD card.

I found though that running your system with the default 100MB swap file under heavy load it will just hang. Only power off, power up will resolve the issue. With the 500 MB swap file your system will run much more stable under heavy load. If you fire up only one application at the time, your Swap file will be rarely used.

And if you are in an emergency situation (the solution is intended for such use) you do not want your system to lock up if you started up too many applications by accident under the stress you are.  It can mean the difference between life and death. 

We pray you will not be under those circumstances for a long time, so your SD card will last for that period. And if you want to be really sure, keep a copy as backup of your SD card.


Install Meld

The application Meld is a visual diff and merge tool.

sudo apt-get install meld


Known issues

If your BT device loses connectivity it will not be able to connect to your device again. In that case you will have to restart your computer or restart your Bluetooth stack.

We would like to get in touch with someone who wants to search a solution for this issue.