Graphical aspect may vary depending on your choices in following the instructions below, but the end result should look something like this:
Here are the steps I took to upgrade my nodes when the time came. Make sure that your apt upgrade and apt dist-upgrade don't have any errors.
Additionally, on one of my nodes, I had to confirm the grub install location. So It may be good to do this prior to upgrading by confirming the mount point of your boot disk.
apt remove --purge r8168-dkms -y
rm /etc/modprobe.d/blacklist-r8169.conf
sudo sed -i 's/GRUB_CMDLINE_LINUX="r8168.aspm=0 r8168.eee_enable=0 pcie_aspm=off loglevel=3"/GRUB_CMDLINE_LINUX=""/' /etc/default/grub
update-grub
My Raspberry Pi 4 kept losing its wlan0 interface. I could usually reconnect via Ethernet but, from time to time, I noticed that the eth0 interface would also go walkabout.
I tried a lot of things but the one described here seems to have cured the problem. I have no idea why it works. It just does.
The script shown in the next step should be created on your Raspberry Pi. Please do not make the mistake of selecting the text, copying it into a text editor on your Windows machine, saving the file, and then moving the file to your Raspberry Pi. Unless you take precautions, Windows will add its 0x0d 0x0a (CR+LF) line endings and those will stop the script from working properly on your Raspberry Pi.
