Problems adding and removing network interfaces

[Supersayano]

It happens that I am trying to delete a network interface, in this case the one in the attached image called 'Julio César'. As you can see, it appears in the list of networks in the tray, but if I then go to the network connections configuration, this 'Julio César' network does not appear, so I cannot delete it as I would wish.



Until yesterday, it did appear in the network connections, then I clicked on delete and it gave an error that I don't remember now but that basically said that it had not been possible to delete it. The fact is that it was deleted from the network connections window, but not from the network list in the tray, as can also be seen in the attached image.



On the other hand... could someone tell me what is this network called 'lo' that appears and that does not let me delete? Is this normal? And I would also like to know why the network interface called 'Conexión cableada' does not appear in the list of networks in the tray.
Thanks and greetings...

[oshunluvr]

Why bother deleting it? However, I can delete one here that I'm not using here.

As far as the "otherhand", it appears you may have two NICs thus two "Cable Connections" maybe? "lo" is your local loopback device. That doesn't show here for me either.

Are you using NetworkManager or systemd-networkd to manage your devices?

[Snowhog]

Let me give my view on this.

Established network connections are connections that have been set up in System Settings > Network > Connections. Wifi signals that aren't hidden will show up in the System Tray Networks widget. Deleting a Wi-Fi connection that is listed in System Settings > Network > Connections can't "remove" it from the System Tray Network widget.

[Supersayano]

Why bother deleting it? However, I can delete one here that I'm not using here.

The reason I want to delete it is because I don't like having superfluous things that can only cause me errors. So, even though I'm very picky, the truth is that I would like to delete that network, because if it no longer exists, it doesn't have to be there. Isn't there a way to delete it?.

As far as the "otherhand", it appears you may have two NICs thus two "Cable Connections" maybe? "lo" is your local loopback device. That doesn't show here for me either.

I do indeed have two network cards on my computer, one is 1 GB and the other is 2.5 GB. Of course the network cable only connects to one of them, but shouldn't the other one appear in the tray, just like it does in the system connections preferences, even if it doesn't have a cable connected?.

Are you using NetworkManager or systemd-networkd to manage your devices?

I don't know that, how can I find out?.

Thanks and regards...

[Supersayano]

Established network connections are connections that have been set up in System Settings > Network > Connections. Wifi signals that aren't hidden will show up in the System Tray Networks widget. Deleting a Wi-Fi connection that is listed in System Settings > Network > Connections can't "remove" it from the System Tray Network widget.

Ok, but why doesn't the 'Conexión cableada' network appear in the list of network interfaces on the tray?. And as for the network interface called 'lo'... what is that and why can't I delete it?.
Thanks and regards...

[oshunluvr]

The answer(s) might be in /etc/netplan/

Copy the contents of whatever file(s) in there and lets have a look.

[oshunluvr]

Looks like the "lo" thing was a bug a few years back. Maybe it's a regression. Luckily, it's fixable.

Navigate to /etc/NetworkManager and open the NetworkManager.conf file with Kate. Then add these lines to the bottom of the file:

[keyfile]
unmanaged-devices=interface-name:lo

and save it. Then restart NetworkManager with this command:

sudo systemctl restart NetworkManager​

You can enter that in Konsole or if you have Dolphin open, just hit F4 and a terminal will open at the bottom of Dolphin.

[Supersayano]

In /etc/netplan/ there are 5 files. One of them called 01-network-manager-all.yaml contains this:

network:
version: 2
renderer: NetworkManager


Does that mean I'm using NetworkManager to manage my devices?.

The other 4 files seem to correspond to one of the network interfaces. I even noticed with horror that the wifi password appears in plain text in them, which I don't know if it's normal. If necessary I'll put the content of said files here by editing the passwords, but I suppose that to find out if I use NetworkManager or systemd-networkd that's enough, right?
Greetings...

[oshunluvr]

Come to think of it, you can do this with your other connection too:

unmanaged-devices=interface-name:Conexión cableada

just below the previous line in the above post.

However, note this removes them from showing in the Networking systray widget but not from the Network Manager interface.

[oshunluvr]

In /etc/netplan/ there are 5 files. One of them called 01-network-manager-all.yaml contains this:

network:
version: 2
renderer: NetworkManager


Does that mean I'm using NetworkManager to manage my devices?.

The other 4 files seem to correspond to one of the network interfaces. I even noticed with horror that the wifi password appears in plain text in them, which I don't know if it's normal. If necessary I'll put the content of said files here by editing the passwords, but I suppose that to find out if I use NetworkManager or systemd-networkd that's enough, right?
Greetings...

I'd be interested in the file list, not necessarily all the contents if they're just interface files. Probably you can delete the one referring to the wifi you don't want to see. And yes, you're using NetworkManager.

[oshunluvr]

AFAIK, there shouldn't be any files in that folder except for netplan configuration.

[Supersayano]

Navigate to /etc/NetworkManager and open the NetworkManager.conf file with Kate. Then add these lines to the bottom of the file:
Code:

[keyfile] unmanaged-devices=interface-name:lo
and save it. Then restart NetworkManager with this command:

Thanks, that worked fine (although the command to restart NetworkManager failed and I had to reboot the computer for it to take effect). Now the 'lo' interface no longer appears in the network connections preferences, which is what I wanted.

Come to think of it, you can do this with your other connection too:
Code:

unmanaged-devices=interface-name:Conexión cableada
just below the previous line in the above post.

In this case I think I explained it wrong. In other words, what I want is for the 'Conexión cableada' network interface to APPEAR in the tray, just as it appears in the network connections preferences window. For some reason that interface does not appear and this has started to happen since yesterday, since before it did appear even though there was never a cable connected to it.
Regards...

[Snowhog]

I even noticed with horror that the wifi password appears in plain text in them, which I don't know if it's normal

I can only say that here, those files do not contain my wi-fi password, plain-text or encrypted.

[Supersayano]

I'm pasting here as an example the content of one of those files ( the file is called 90-NM-1a56b9bc-f1ca-48d1-bed0-695ba447b6e3.yaml ) with the password obviously edited:

network:
  version: 2
  wifis:
    NM-1a56b9bc-f1ca-48d1-bed0-695ba447b6e3:
      renderer: NetworkManager
      match: {}
      dhcp4: true
      dhcp6: true
      ipv6-address-generation: "stable-privacy"
      access-points:
        "74;117;108;105;111;32;67;195;169;115;97;114;32;53;71;45;50;":
          auth:
            key-management: "psk"
            password: "XXXXXXXXXXXXXXXXXXXX"
          networkmanager:
            uuid: "1a56b9bc-f1ca-48d1-bed0-695ba447b6e3"
            name: "Julio César 5G-2"
            passthrough:
              connection.autoconnect: "false"
              ipv6.ip6-privacy: "-1"
              proxy._: ""
      networkmanager:
        uuid: "1a56b9bc-f1ca-48d1-bed0-695ba447b6e3"
        name: "Julio César 5G-2"

XXXXXXXXXXXXXXXXXXXX would be the password that I have obviously edited by changing it to the X's.
Regards...

[Virginio Miranda]

On the other hand... could someone tell me what is this network called 'lo' that appears and that does not let me delete? Is this normal? And I would also like to know why the network interface called 'Conexión cableada' does not appear in the list of networks in the tray.
Thanks and greetings...

Io is a loopback interface and is a virtual interface. It is not linked to any kind of physical or other logical interface. It can be used for routing protocol to paths for a device. Several programs can use this, like antivirus, a Cloud or a Firewall for example. A 127.0.0.1 or Localhost is one of the usage. It is not necessary to disable or uninstall this.