A bug has been discovered where if your PC was originally installed with a fairly old version of Endless, and then updated to the latest version, your apps (such as the Chromium web browser or the Steam gaming platform) that run in a Flatpak environment may be unable to establish network connectivity.
The precise range of affected Endless OS installations has not been determined, however it has been verified that installations that originated from Endless OS 3.0 are affected.
The occurance of the bug is related to the timing of you logging into the session, and the timing of your network connectivity becoming established.
If you are affected, your apps will not be able to get online. Each app will report the connectivity issue differently. For example, the Chromium web browser would report:
This site can’t be reached
www.google.com’s server IP address could not be found.
When the problem occurs, it will affect all apps that run using the Flatpak environment.
The problem will only occur if your computer had not automatically established a network connection at the point when you logged into your user account (e.g. if your network is slow to connect, or if you needed to login first in order to set up the network connectivity, or if your network connection profile is tied to your user session instead of being systemwide).
Open a Terminal and run:
stat -c %F /etc/resolv.conf
If the result is symbolic link then you are likely to be affected by this issue.
For now, a manual terminal command must be entered to solve the issue. We hope to provide an automatic, hands-off solution in future.
From a user account with Administrator privileges, open the Terminal app and run the following command:
sudo sed -i '' /etc/resolv.conf
You may be prompted for your user account password. Your password may not appear as you type it in, but if prompted, type it in anyway and press enter.
Running this command will produce no output, it will just return you to the terminal prompt. This is normal. It may seem like it has not done anything, but it will have made the relevant change behind-the-scenes.
Finally, log out of your user account, and then login again.
This information is presented for technicians and developers. You do not need to study this section in order to resolve the issue.
Flatpak's session-helper maintains a copy of /etc/resolv.conf and other important files at /run/user/1000/.flatpak-helper/monitor. It aims to dynamically update the copies of such files when the original files change. It also aims to handle the situation where the original files are symlinks, but unfortunately there is a limitation here, if the symlink points at a file that doesn't exist (because e.g. NetworkManager has not yet established a connection) then that file will be absent during the entire session. Flatpak bug report #4268 has been filed accordingly, and we will update the Endless OS flatpak version once a fix is available.
Old versions of NetworkManager, such as the version 1.2 shipped with Endless OS 3.0, create /etc/resolv.conf as a symlink when network connectivity is established. Modern versions of NetworkManager such as version 1.30 shipped in Endless OS 4 will ordinarily create and maintain /etc/resolv.conf as a regular file, however it is explicitly documented that it will be retained as a symlink if it is found to be in that state, which it will be for those old installations.