Network setup
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NTP
Network time protocol, to keep clocks in sync. At DTU most clock sources are blocked, the clock source needs to be configured.
At DTU, edit /etc/ntp.conf (or maybe /etc/ntpsec/ntp.conf), add ntp.ait.du.dk to server pool
sudo nano /etc/ntpsec/ntp.conf
... # Use servers from the NTP Pool Project. Approved by Ubuntu Technical Board # on 2011-02-08 (LP: #104525). See http://www.pool.ntp.org/join.html for # more information. pool ntp.ait.dtu.dk ...
Sync time (if on DTU net)
sudo ntpdate -u ntp.ait.dtu.dk
Should work in and around DTU - see also NTP howto for more details.
WiFi network
Now open wpa_supplicant.conf
sudo nano /etc/wpa_supplicant/wpa_supplicant.conf
If you added an wifi access point, it probably looks something like this
network={ ssid="device" key_mgmt=NONE }
or using typical security with a password
network={ ssid="tdc432" psk="secret_password" key_mgmt=WPA-PSK id_str=home }
You can add any number of the "network" groups for all the networks you get across If you don't like the network password to be visible, see guide below.
Private network
Generate encrypted key with
wpa_passphrase mySSID secret776
if the desired SSID is "mySSID" and the password is "secret776", then copy the result into /etc/wpa_supplicant/wpa_supplicant.conf (except the line with the password in clear text).
network={ ssid="mySSID" #psk="secret776" psk=812439e952156aea9983f3df5a389cf3f9c2e9f30ae2624eaad1551612a6ef71 }
Eduroam or DTU secure
When connecting to Eduroam you will eventually have to type in your username and password in the wpa_supplicant.conf-file. In order for your password not to be visible, generate a hash-code for it
echo -n password_here | iconv -t utf16le | openssl md4
Copy the hash-code and then clear the terminal window and the command history
clear history -c
Now open wpa_supplicant.conf
sudo nano /etc/wpa_supplicant/wpa_supplicant.conf
Add or replace the following (You need at least one network group)
country=DK ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev ctrl_interface_group=0 update_config=1 network={ ssid="eduroam" scan_ssid=1 key_mgmt=WPA-EAP eap=PEAP phase2="auth=MSCHAPV2" identity="username" password=hash:your_hash_code } network={ ssid="DTUsecure" scan_ssid=1 key_mgmt=WPA-EAP eap=PEAP phase2="auth=MSCHAPV2" identity="username" password=hash:your_hash_code }
Replace username with your username on Eduroam, i.e. your student number and replace your_hash_code with the hash-code you generated in the previous step.
Reboot the Raspberry Pi
sudo reboot or sudo /etc/init.d/networking restart
Check IP and SSID
When the Pi has rebooted, connect to it using SSH once again. Check that the Pi is connected to WiFi
ifconfig
Under wlan0 confirm that the Pi has received an IP (inet addr) and note down the first three sections of the IP - they are most likely 10.16.175.xxx
To see which SSID you are connected to use
iwconfig
The MAC address ('HWaddr' or 'ether') of the Pi should also be noted down - this probably starts with B8:27:EB:xx:xx:xx make sure to get all of it.
Find IP of robot (Linux)
In case the Pi gets a new IP address after reboot, you can search for it using the MAC address and nmap. If nmap is not installed, start by installing it
sudo apt-get install nmap
To search for the Pi using the MAC address in terminal type
nmap -sP 10.16.175.0/24 | awk '/^Nmap/{ip=$NF}/B8:27:EB:23:A0:F5/{print ip}'
where 10.16.175 is the first three sections of the IP you noted down and B8:27:EB:23:A0:F5 is the MAC address of the Pi. This should return the IP of the Pi.
NB! the MAC can hold letters, they should probably be capital.
If you don't know the MAC address
Use the first part, to get a list of active IP on the net:
nmap -sP 10.16.175.0/24
The name of the robot should be included in the list, but it can take a while for the network to detect the name.