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Neil Bothwick spends most of his time correcting the editor.

Q  Confused network card

I’ve been using Linux Mint Cinnamon flavour for many years. I recently decided to update from version 18.3 to the latest 20.x version. I went through the procedure of going from 18.x to 19.0, then to 19.3 finally to 20.0 ensuring that I had backups and snapshots readily available.

The update to version 20 failed abysmally, with no network connection and to make matters worse, substantial loss of data. I reverted to 19.3 but still had problems. The cause was eventually traced to the kernel in use as follows:

Linux kernel 5.0.0-32-generic amd64 (End of Life) Everything works OK, network connects.

Linux kernel 5.3.0-70-generic amd64 (End of Life) Everything works OK, network connects but shows battery symbol, “Using battery power"!

Linux kernel 5.4.x-xx-generic amd64 (all versions) Apps work as long as no network/internet required as no network connection, shows battery symbol as above.

I’m now using the 5.3.70 kernel despite the battery symbol. Is this a known problem? My network adaptor looks pretty standard to me. And why the battery symbol – this is a desktop mains powered PC? Or is the battery referred to the one in the keyboard/mouse, in which case there should be two!

John Oliver

A This is probably a driver conflict. There are two separate drivers for this network chipset: r8168 and r8169. The r8168 driver is a third-party module that was the standard way of using these Ethernet adaptors, but now the kernel’s built in r8169 driver is the better option. I see from the information you provided that the 5.3.70 kernel, which works, is using the r8169 driver. You need to make sure this is the case for all kernels. Because r8168 is a third-party driver, the simplest option is to uninstall the r8168 package. You should also make sure than any related rules in /etc/modules.d are removed.

If the adaptor continues to not appear with the later kernel, check the system journal with this terminal command

 $ sudo journalctl -b | grep r816

This will show the kernel detecting the Ethernet adaptor and loading, or trying to load, a driver for it.

As for the battery issue, if you open a terminal and run

 $ upower --dump 

you’ll see what the system thinks you have in terms of batteries. It’s most likely your mouse battery being seen, but do check. The warning does no harm, and you can remove the battery applet on a desktop machine. However, do check your power management settings – you don’t want your computer to suddenly hibernate just because your mouse battery is getting low!