Cannot connect to "shared" ipv4 network ("Error: Connection activation failed: IP configuration could not be reserved (no available address, timeout, etc.)"

[Tyler Johnson]

I have a connection profile which is supposed to allow my computers to talk to eachother over an ad-hoc ethernet connection. For me, this is mostly useful for when I need to transfer large files over from one computer to another (the only network I have is WiFi, and it's painfully slow). So, If I need to transfer files from machine A to machine B, I just use an ethernet cable. Easy-peasy.

However, after upgrading one of my machines from Ubuntu 16.04 to 18.04, I find that said machine can no longer create such a network. If I try to active the profile graphically using nm-applet, it fails without displaying any error messages. However, If I try to activate it from the command line with "nmcli con up id Wired\ Connection\ 2", it fails with the following message:

Error: Connection activation failed: IP configuration could not be reserved (no available address, timeout, etc.)

While typing this bug report, I ran the "ubuntu-bug network-manager" command, and will post the results below. If there's anything else I can do (I can't read/write code very well, but I can test code, and get any additional information, so long as I'm given clear instructions on how to do so), please let me know.

[Tyler Johnson (tsjswimmer)]

BTW, I forgot to mention a few things:

I haven't had this issue with Arch GNU/Linux, so I'm guessing this is NOT an upstream issue. Then again, I haven't tried doing this on Arch in quite a while, and I don't think I can attempt it now because the computer in question is having some hard drive issues. I'll test once said issues are fixed.

I also forgot to add that - as far as I know - this bug only affects 18.04. THis bug doesn't seem to affect 16.04, nor does this bug affect Debian Squeeze.

Also, I'm running the x86_64 version of Ubuntu.

lshw lists my ethernet hardware as "82577LM Gigabit Network Connection", manufactured by "Intel Corporation". The driver is "e1000e", revision "3.2.6-k", firmware "0.12-1".

[Ajay Kanse (ajkan001)]

Hi Guys

I am facing this issue after lubuntu bionic install. Does anyone know how to resolve this issue ?

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Tyler Johnson (tsjswimmer)]

@ajkan001:

Actually, I think I did. Apparently, 18.04 needs dnsmasq to be running, whereas 16.04 didn't seem to require the user to even have dnsmasq installed. So, make sure you have dnsmasq installed, using (without quotes) "sudo apt install dnsmasq-base". Sometimes, however, dnsmasq just doesn't want to play nice. In that case, use (again, without quotes) "sudo pkill -x dnsmasq" or "sudo killall dnsmasq" (either one will work), and try again.

PS: I probably should have mentioned something on this bug report before, but I guess I forgot. My apologies.