Ubuntu boots saying network cable unplugged when it's not

Recently I set up my PC with Xubuntu 16.04.2 and so far I am more than happy with it, except for one thing.

That is the networking. Sometimes (not always for some reason) the system boots and the network interface shows as UP but it doesn't work. I configured it with DHCP during installation and ifconfig just pretends there is no network cable plugged in, even though I never removed it.

Now I have two ways of solving this, when it happens. Either I go to the back of my computer and re-plug the cable or I go to the system tray and dis- and enable the networking. I think I also tried sudo service networking restart once, which I think also worked.

My setup is a Gigabyte GA-Z97X-UD3H motherboard which has a Intel I217-V ethernet controller on-board, according to lspci.

Does someone who what's wrong? I found this topic on the forum here where someone had a similar problem, but his solution didn't work for me yet. I tried it and at first it seemed to work, but this morning it stopped working again.

For completeness here is my current version of the two files that are mentioned in that post. I left them the way they were created from the installation but changed the things mentioned in the forum post.

$ cat /etc/NetworkManager/NetworkManager.conf
[main]
plugins=ifupdown,keyfile,ofono
dns=dnsmasq

[ifupdown]
managed=true

And

$ cat /etc/network/interfaces
# interfaces(5) file used by ifup(8) and ifdown(8)
auto lo
iface lo inet loopback

auto eno1
iface eno1 inet dhcp

Any help is highly appreciated! Thanks!

Yeah there is some kind of a bug with the network manager in Ubuntu 16.04 releases.
Rebooting the network manager seems to work for a while.
But i personally just upgraded to the 16.10 version of the Ubuntu familly distributions.

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Did that fix the issue?

For me it did, had no issues with the network manager anymore.
You could try to download Xubuntu 16.10 iso trow it on a usb drive and boot from it,
use the live envoirement and see if you experiance the same issue or not.

Maybe that might be worth a try?
Then you dont have to re-install the system just yet.

I will make a backup image of my boot drive and then just try to upgrade it to 16.10.

If it doesn't work, I will just copy the backup back :D

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Thats also an option of course.
You could also jump into the Ubuntu forums and see what they have to say about it.
But yeah my thought was, if you just use a live image for testing,
then you dont have to mess with your system on first hand.

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