What network services are restarted when a PC is shutdown?

Question

I am running Linux Mint and if I switch from a wireless connection to a wired connection, then I am unable to connect to the internet.

It will give me the notification that I'm wired to a network, but pages won't load.

Now, if I restart my laptop then my internet works again on a wired connection.

I have tried using

$ sudo systemctl restart networking

and

$ sudo /etc/init.d/networking restart

But none of them seem to be doing whatever restarting my PC does. What are some commands I should try to restart my networking services whenever I can't connect to the internet when I switch from a wireless connection to a wired one?

If it's relevant, I use a VPN.

Answer 1

If your system is using NetworkManager, then sudo systemctl restart networking is likely to do nothing useful and might even work against NetworkManager, depending of exactly how your system is configured.

As a background, the networking.service uses the legacy ifup/ifdown commands and their /etc/network/interfaces configuration file. When NetworkManager is in use, you don't need that: NetworkManager can read its configuration directly from /etc/network/interfaces, from the /etc/NetworkManager/system-connections/ directory, from per-user network settings stored by your desktop environment, and/or from the netplan subsystem in modern Ubuntu/Mint.

If your VPN connection is also integrated with NetworkManager, it should be automatically restarting the VPN connection if needed. So I'm guessing you're using a VPN client that is either a separate product that does not have full NetworkManager integration, or you've configured it in a way that bypasses NetworkManager.

You should determine which service(s) are related to your VPN connection, and attempt to restart those after changing from a wireless connection to a wired one, or vice versa.

There are so many different VPN implementations on the market that it is frankly impossible to give universal instructions without knowing more details. Is your VPN based on IPsec, L2TP, OpenVPN, Wireguard or is it some proprietary product? How did you configure it, and how do you operate it normally?