Networking – How can I prioritize Ethernet over Wi-Fi on Ubuntu 18.04?


Precede Ethernet over wireless connections when the Ethernet cable is connected


After googling and reading a good deal, I've come to a point where I am believe What I should do is something like

nmcli change connection [id-of-ethernet-interface] ipv4.route-metric 200
nmcli change connection [id-of-ethernet-interface] ipv6.route-metric 200

Here, 200 is a lower value than the wireless metric for Ethernet to override wireless communication.


What baffles me is the reports I get route -n After I've run the above commands and done a reboot (for a good measure), and the fact that this does not seem to accomplish the achievement of my goal

$ route -n
Kernel IP routing table
Destination Gateway Tag Ref Defaults to Iface
0,0,0,0 123,456,89,1 0,0,0,0 UG 600 0 0 wlp1s0 123.456.89.1 UG 20200 0 0 enp0s31f6
123.456.89.0 U 200 0 0 enp0s31f6
123.456.89.0 U 600 0 0 wlp1s0
654.321.0.0 U 1000 0 0 enp0s31f6

The numbers add up in terms of my command execution, but for the lines that say so 123.456.89.1 UG 20200 0 0 enp0s31f6
654.321.0.0 U 1000 0 0 enp0s31f6

The first line is preceded by 20 before the 200 value I set. This is applied consistently, depending on what I have done. If I change the value for the metric nmcli 500 to say route -n will report 20500. Why is this happening? It certainly does not look right, as I said I wanted either 200 or 500, not 20200 and 20500.

The second line has a metric value of which I have no idea where it comes from, and I can not influence it at all. If anyone can shed light on this topic, I am grateful.

It does not look as if these commands would end up in something tangible except the metrics. I can not say that ethernet has priority, so I assume that this is not the case.

Other findings

What I found curious and apparently working something so far is the use of $ sudo ifmetric dep0s31f6 200, That makes two or three things;

  • It influences the metric of the interface (route -n reports all lines with the Ifaceenp0s31f6 have the value 200)
  • It affects the user interface in Ubuntu (In the top right corner, I see a visual switch between Ethernet and Wi-Fi icons, depending on the metric values ​​I provide in ifmetric Command)
  • It sometimes interjects NETLINK: Error: file exists Mistake with me. Subsequent executions of the same command can or can do not lead to this error

Some system information

  • EliteBook 850 G5
  • Ubuntu 18.04
  • The Ubuntu installation was made by having the installer use the entire CD, enabling encryption, enabling third-party driver downloads, and so on.

18.04 – Lock screen – turn off

How do I add the drop-down menu when the computer is locked? There is now only the "suspend" button.
I want other users to log out (without having to enter my password) and then restart another system

Update: I am only a user for this particular installation, and the login screen is incorrect.

Eclipse boot error on Ubuntu 18.04

I've just installed the Eclipse IDE, but there seems to be an error running Eclipse.exe.

Here is the log file:

! SESSION Wed 28.11 18:42:12 IST 2018 —————————————- –
! ENTRY org.eclipse.equinox.launcher 4 0 2018-11-28 18: 42: 12.757
! MESSAGE exception when starting the Eclipse platform:
java.lang.ClassNotFoundException: org.eclipse.core.runtime.adaptor.EclipseStarter
at java.base / (
in java.base / java.lang.ClassLoader.loadClass (
in java.base / java.lang.ClassLoader.loadClass (
at org.eclipse.equinox.launcher.Main.invokeFramework (
at org.eclipse.equinox.launcher.Main.basicRun (
at (
at org.eclipse.equinox.launcher.Main.main (

what should I do?

Networking – Recv-Q is not empty for UDP sockets on Ubuntu 18.04

Since upgrading to Ubuntu 18.04 (already half a year), I still see that Recv-Q is never empty for many UDP sockets. The same picture shows DigitalOcean VPS when I upgraded it to Ubuntu 18.04. Ubuntu 16.04 and 17.10, which I have tested, are doing well.

These non-empty UDP receive queues result in UDP datagrams not being received on receipt or only delayed.

I just did it

sudo apt-get update
Sudo apt-get upgrade

but it did not help.

$ lsb_release -a

Distributor ID: Ubuntu
Description: Ubuntu 18.04.1 LTS
Publication: 18.04
Code name: Bionic

$ uname -a

Linux 4.15.0-39-generic # 42-Ubuntu SMP Tue 23.10. 15:48:01 UTC 2018 x86_64 x86_64 x86_64 GNU / Linux

$ netstat -lup

(Not all processes could be identified, no process information is displayed that is not owned by the company, you would need to be root to see all the information.)
Active Internet connections (server only)
Foreign address of the local address of Proto Recv-Q
State PID / program name
udp 4096 0*
udp 0 0* -
udp 0 0* -
udp 5120 0 localhost: 43804* -
udp 5120 0 blade-HP-ProBook-: 44807* -
udp 0 0 Blade-HP-ProBook-: 44926* -
udp 0 0 localhost: 37844* -
udp 42240 0* -
udp 0 0 Blade HP ProBook: 46481* -
udp 0 0* -
udp 8448 0* -
udp 0 0* -
udp 8448 0* -
udp 41472 0 localhost: domain* -
udp 0 0* -
udp 18432 0* -
udp 0 0 blade-HP-Pro: netbios-ns* -
udp 18432 0* -
udp 7680 0* -
udp 0 0 Blade-HP-Pr: Netbios-dgm* -
udp 7680 0* -
udp 0 0* -
udp 0 0* -
udp 5120 0* 2386 / Dropbox
udp 10240 0 2386 / Dropbox
udp 0 0* -
udp6 49152 0 [::]: mdns               [::]: * -
udp6 0 0 [::]: 50237              [::]: * -   

I've been waiting for the problem to resolve, but it seems nobody else has this problem.
Can someone help me please?

DHCP conflicts on two Ubuntu 18.04 servers

I have two machines running Ubuntu 18.04 Server Edition. Networking goes through netplan, You get your IPv4 from a DHCP server v6.3 running on Windows Server 2012 R2. For some reason, they do not specify a MAC address but a very long hardware type. For some reason, both computers give the same client ID. Then the DHCP responds with the same IP address, resulting in IP conflicts on my network. I have issued DHCP requests when booting both computers:

We can see these machines e0: d5: 5e: b0: ed: 49 and e0: d5: 5e: 8f: a6: b0 Both specify the same client ID. What's up with my Ubuntu server configuration?

How do I use Konqueror in Ubuntu 18.04 LTS?

I found Konqueror very good if you want to organize a lot in your own data (copy, move, map, etc.). In Nautilus you can not see the full directory structure (actually only one, the current one). So in Nautilus you need two or even more windows to keep track.

My problem:
I completely rearrange my files in a new directory tree based on the 5-folder principle (eg, 2.3.1 to 2.3.5), so I have to rearrange old files in this new structure. I need to know if a file should be copied where it needs to be stored. In Konqueror I see the directory tree and can choose between several candidates.

Who knows a practical solution?

Upgrade to 18.04 with Ubuntu wiki

I'd like to try MythTV, but at first it seems I should upgrade from 16.04 to 18.04. Using the Ubuntu Wiki BionicBeaver / ReleaseNotes "The first step is to open the" Software & Updates "setting in the system settings, but I can not find" Software & Updates "in the system settings. There are many sources for this information, all a little bit different.I assumed that the Ubuntu wiki would be the best curated (near the source). Is that so? Can anyone provide a more reliable method for an upgrade recommend.

Unity mode is missing in Ubuntu 18.04 LTS

I recently installed the VMware Workstation 15 Player on my Ubuntu 18.04 LTS laptop and Windows 7 as the guest operating system. I have Vmware Tools installed and everything seems to be fine. I wanted to try the Unity mode, but under Virtual Machine -> Virtual Machine Settings -> Options I do not find it. I've seen a lot of help documentation and every article says Unity mode is available in the options menu. Why do not I see it? What do I miss?

grub2 – Problem with the dual-boot of Windows 10 and Ubuntu 18.04

I had a dual boot computer with Windows 10 and Ubuntu 18.04.

Last month I decided to uninstall and reinstall Ubuntu for a variety of reasons. I have completely deleted the hard drive Ubuntu partition and also deleted Grub. But when I restarted my computer, somehow I still saw the Grub console. To leave that, I had to type exit three times to start in Windows. I followed a guide and tried to install Ubuntu with Unetbootin but could not. Besides, I could not even boot into Windows right now. Instead, I got an error message saying that I damaged the hard drive. Then I installed Windows 8 (with a CD) on my computer to access Windows 10. Now I have Windows 8 and Windows 10 on my computer. While booting, I get the Windows Bootloader screen with 3 options -> Windows 10, Windows 8, Unetbootin.

Now I want to install and install Ubuntu 18.04 properly Uninstall Windows 8 from my pc. Please help me. I am an absolute newcomer to Ubuntu and Linux.
Many Thanks.

18.04 – Do not force Oracle Java 10 Java 11

The Linux Uprising ppa is currently forcing us to release version 11 of Java.

sudo add-apt-repository ppa: linuxuprising / java

That's nice, I like being modern and up to date, but I have an app that only works with Java 10.

webUpD8 stopped after 9 and Linux Uprising started at 10 and that worked (apparently …, personally I have never tested it) until they released 11 and now when you enter the following:

sudo apt install oracle-java10-installer

you get :

Read package lists ... Done
Create dependency tree
Status information is read ... Done
The oracle-java10-installer package is not available, but is referenced by another package.
This may mean that the package is missing, outdated or
is only available from another source

E: package & oracle-java10-installer & # 39; has no installation candidate

just type:

sudo apt install oracle-java11-installer 

will work. This is the package referred to above.

clearly something was done that was a bit sloppy:

what are my options