Overall process to install Ubuntu Server 16.04 on a Raspberry Pi 3 Model B.
Insert the microSD card 1
sudo fdisk -l
sudo fdisk /dev/mmcblk0
# then d (all), n, p --> yes, t, b (FAT32), w
sudo mkfs.vfat /dev/mmcblk0p1
Copy the Ubuntu server image to the card 2
xzcat ~/Downloads/ubuntu-16.04-preinstalled-server-armhf+raspi3.img.xz | sudo dd of=/dev/mmcblk0 bs=4M
sync
Insert the card into the Raspberry and boot it with an ethernet connection available.
Upgrade packages 3
ssh ubuntu@192.168.x.x
# password update
sudo apt-get update
sudo apt-get upgrade # wait...
Mount the SDCard into a PC and update the root file config.txt from:
...
device_tree_address=0x100
device_tree_end=0x8000
...
to
...
device_tree_address=0x02008000
...
Reboot the Raspberry and all must be ok.
Configure the automatic wifi connection
Install wpasupplicant to the system.
sudo apt install wpasupplicant
Edit the file located /etc/wpa_supplicant/wpa_supplicant.conf to add the following lines:
# allow frontend (e.g., wpa_cli) to be used by all users in 'wheel' group
ctrl_interface=/sbin/wpa_supplicant
# home network; allow all valid ciphers
network={
ssid="[SSID]"
scan_ssid=1
key_mgmt=WPA-PSK
psk="[PSK]"
}
Update the network interfaces to use this configuration
Decrease the boot connection delay to several seconds 4 (useful for testing):
sudo vi /etc/systemd/system/network-online.targets.wants/networking.service
# TimeoutStartSec=20sec
sudo systemctl daemon-reload
sudo /etc/init.d/networking restart
ifconfig
# Check that the wireless interface has an attached IP