Installing Ubuntu LTE over serial console on APU board

Posted on 

Installing Ubuntu on APU boards is easy if you know the steps. Other tutorials are recommending modification of the ISO file that is time-consuming and totally unnecessary. 

Step 1:

Download Ubuntu Server LTS (amd64) image from here: https://ubuntu.com/download/alternative-downloads

At the time of writing, I'm using version 20.04.2. The full image name is ubuntu-20.04.2-live-server-amd64.iso

Step 2:

Flash the image on USB. 

If you are using Linux, use dd:

sudo dd if=ubuntu-20.04.2-live-server-amd64.iso of=/dev/sdX; sync

sdX needs to be replaced with sdb, sdc, sdd or similar. Do not include a number. If you flash "sdb1" it won't work.

if you are using Windows, flash the image using Rufus: https://rufus.akeo.ie/

Step 3: 

Insert the USB into the APU board, and use putty to connect over the serial cable, as described here.

Step 4: 

Ubuntu installer will boot, but it will complain that the graphics card is not detected. The error will look similar to this

graphics initialization failed
Error setting up gfxboot

This is expected because APU does not have a graphics card. The installation needs to be done through the serial console. You will get a boot: prompt. The command to type is 

live console=ttyS0,115200n8

After you press enter, you may get two warnings similar to this

[    4.441954] sd 0:0:0:0: [sdb] No Caching mode page found
[    4.447545] sd 0:0:0:0: [sdb] Assuming drive cache: write through

Don't be concerned. This is nothing to worry about. After a minute, you should get an installation menu similar to this, and you can proceed as you would on hardware that has a graphics card.

Continue in basic mode and follow the instructions on the screen. That's it. 

Use Tab, Arrow Up, Arrow Down to switch between different options. Use the space bar to select/deselect checkboxes.

Toubleshooting

If you see "Sorry, there was a problem completing the installation", you probably have pfSense or OPNsense installed on the SSD drive. 


For some reason, Ubuntu doesn't want to override filesystems it doesn't recognize. You will have to clean up the SSD before Ubuntu can be installed. Fortunately, the installer allows us to drop into shell to do just that. Use the Help menu in the upper right corner and choose "Enter shell". After that, you can type the following command to clean the SSD. This command will clean up the first 4MB of the drive, so it will look to the installer like a fresh SSD without any partitions.

dd if=/dev/zero of=/dev/sda bs=4M count=1;
exit

And try again


Tip: check out many similar articles in our Knowledge Base.


TekLager specializes in selling open source hardware for building routers, firewalls and other network appliances.

Wle200nx_WiFi_Kit

wle200nx wireless WiFi kit

TekLager Compex wle200nx wireless WiFi kit for routers. Qualcomm Atheros AR9280. Works well with pfSense
356 SEK 2099-01-01 356 SEK
445.00 SEK incl. vat
APU2E4_ROUTER_VOLUME

APU2E4: 3x Gigabit LAN, Quad Core CPU, 16GB SSD, 4GB RAM

TekLager PC Engines APU2E4 is a state of the art router / firewall for office or home. Ships pre-configured, optimized and ready to use. Compatible with pfSense, IPFire, OPNSense and others.
1,882 SEK 2099-01-01 1,882 SEK
2352.50 SEK incl. vat
APU4D4_ROUTER

APU4D4: 4x Gigabit LAN, Quad Core CPU, 16GB SSD, 4GB RAM

TekLager APU4D4 Router/Firewall. 4x Gigabit NIC, Quad-Core CPU, 16GB SSD, 4GB RAM. Compatible with pfSense, IPFire, OPNSEnse and others.
2,073 SEK 2099-01-01 2,073 SEK
2591.25 SEK incl. vat
TLSENSE-i7-7500U

TLSense 7500U: 6x Gigabit LAN, 7th gen i7 CPU, 128GB SSD, 16GB RAM

TekLager TLSense i7 7500U: 6x Gigabit LAN, 7th gen i7 CPU, 128GB SSD, 16GB RAM
6,972 SEK 2099-01-01 6,972 SEK
8715.00 SEK incl. vat