Network Manager Connectivity Check problem?

[popey]

Dunno if this is a bug or infrastructure problem.

I’m on Kubuntu and keep getting a pop up telling me I have “limited connectivity” on my wired desktop computer. I initially thought it’s entirely possibly my home network or ISP is at fault.

However, upon learning how it works, I noticed two things.

Firstly, the configuration in /usr/lib/NetworkManager/conf.d/20-connectivity-ubuntu.conf has a weird (to me) URL with a dot in it.

alan@robot:~$ cat /usr/lib/NetworkManager/conf.d/20-connectivity-ubuntu.conf 
[connectivity]
uri=http://connectivity-check.ubuntu.com./

That doesn’t look right.

However, that may not be it, because there appears to be a separate issue. If you try and visit that URL, sometimes it works and sometimes it doesn’t. This isn’t down to my network, because I’ve had friends try it too, and they have the same problem.

With or without the dot, sometimes it works, sometimes not, which makes me think it’s a Canonical infrastructure issue. Given it sometimes times out, giving no response, I can see why Kubuntu thinks I have “Limited connectivity”.

A very simple “hit the URL 10 times” with for i in {1..10}; do wget http://connectivity-check.ubuntu.com/; done results in wildly different results, from 1 second to 15 seconds.

• Is anyone else seeing this?
• Why does the URL have a dot in it?

--2022-02-17 13:38:13--  http://connectivity-check.ubuntu.com/
Resolving connectivity-check.ubuntu.com (connectivity-check.ubuntu.com)... 35.232.111.17, 35.224.170.84
Connecting to connectivity-check.ubuntu.com (connectivity-check.ubuntu.com)|35.232.111.17|:80... failed: Connection timed out.
Connecting to connectivity-check.ubuntu.com (connectivity-check.ubuntu.com)|35.224.170.84|:80... connected.
HTTP request sent, awaiting response... 204 No Content
2022-02-17 13:40:25 (0.00 B/s) - ‘index.html’ saved [0]

alan@robot:~$ for i in {1..10}; do wget http://connectivity-check.ubuntu.com/; done
--2022-02-17 13:46:29--  http://connectivity-check.ubuntu.com/
Resolving connectivity-check.ubuntu.com (connectivity-check.ubuntu.com)... 35.232.111.17, 35.224.170.84
Connecting to connectivity-check.ubuntu.com (connectivity-check.ubuntu.com)|35.232.111.17|:80... connected.
HTTP request sent, awaiting response... 204 No Content
2022-02-17 13:46:30 (0.00 B/s) - ‘index.html’ saved [0]

--2022-02-17 13:46:30--  http://connectivity-check.ubuntu.com/
Resolving connectivity-check.ubuntu.com (connectivity-check.ubuntu.com)... 35.224.170.84, 35.232.111.17
Connecting to connectivity-check.ubuntu.com (connectivity-check.ubuntu.com)|35.224.170.84|:80... connected.
HTTP request sent, awaiting response... 204 No Content
2022-02-17 13:46:31 (0.00 B/s) - ‘index.html’ saved [0]

--2022-02-17 13:46:31--  http://connectivity-check.ubuntu.com/
Resolving connectivity-check.ubuntu.com (connectivity-check.ubuntu.com)... 35.224.170.84, 35.232.111.17
Connecting to connectivity-check.ubuntu.com (connectivity-check.ubuntu.com)|35.224.170.84|:80... connected.
HTTP request sent, awaiting response... 204 No Content
2022-02-17 13:46:31 (0.00 B/s) - ‘index.html’ saved [0]

--2022-02-17 13:46:31--  http://connectivity-check.ubuntu.com/
Resolving connectivity-check.ubuntu.com (connectivity-check.ubuntu.com)... 35.224.170.84, 35.232.111.17
Connecting to connectivity-check.ubuntu.com (connectivity-check.ubuntu.com)|35.224.170.84|:80... connected.
HTTP request sent, awaiting response... 204 No Content
2022-02-17 13:46:47 (0.00 B/s) - ‘index.html’ saved [0]

--2022-02-17 13:46:47--  http://connectivity-check.ubuntu.com/
Resolving connectivity-check.ubuntu.com (connectivity-check.ubuntu.com)... 35.232.111.17, 35.224.170.84
Connecting to connectivity-check.ubuntu.com (connectivity-check.ubuntu.com)|35.232.111.17|:80... connected.
HTTP request sent, awaiting response... 204 No Content
2022-02-17 13:46:47 (0.00 B/s) - ‘index.html’ saved [0]

--2022-02-17 13:46:47--  http://connectivity-check.ubuntu.com/
Resolving connectivity-check.ubuntu.com (connectivity-check.ubuntu.com)... 35.224.170.84, 35.232.111.17
Connecting to connectivity-check.ubuntu.com (connectivity-check.ubuntu.com)|35.224.170.84|:80... connected.
HTTP request sent, awaiting response... 204 No Content
2022-02-17 13:46:51 (0.00 B/s) - ‘index.html’ saved [0]

--2022-02-17 13:46:51--  http://connectivity-check.ubuntu.com/
Resolving connectivity-check.ubuntu.com (connectivity-check.ubuntu.com)... 35.232.111.17, 35.224.170.84
Connecting to connectivity-check.ubuntu.com (connectivity-check.ubuntu.com)|35.232.111.17|:80... connected.
HTTP request sent, awaiting response... 204 No Content
2022-02-17 13:46:51 (0.00 B/s) - ‘index.html’ saved [0]

--2022-02-17 13:46:51--  http://connectivity-check.ubuntu.com/
Resolving connectivity-check.ubuntu.com (connectivity-check.ubuntu.com)... 35.232.111.17, 35.224.170.84
Connecting to connectivity-check.ubuntu.com (connectivity-check.ubuntu.com)|35.232.111.17|:80... connected.
HTTP request sent, awaiting response... 204 No Content
2022-02-17 13:46:52 (0.00 B/s) - ‘index.html’ saved [0]

--2022-02-17 13:46:52--  http://connectivity-check.ubuntu.com/
Resolving connectivity-check.ubuntu.com (connectivity-check.ubuntu.com)... 35.232.111.17, 35.224.170.84
Connecting to connectivity-check.ubuntu.com (connectivity-check.ubuntu.com)|35.232.111.17|:80... connected.
HTTP request sent, awaiting response... 204 No Content
2022-02-17 13:46:52 (0.00 B/s) - ‘index.html’ saved [0]

--2022-02-17 13:46:52--  http://connectivity-check.ubuntu.com/
Resolving connectivity-check.ubuntu.com (connectivity-check.ubuntu.com)... 35.224.170.84, 35.232.111.17
Connecting to connectivity-check.ubuntu.com (connectivity-check.ubuntu.com)|35.224.170.84|:80... connected.
HTTP request sent, awaiting response... 204 No Content
2022-02-17 13:46:53 (0.00 B/s) - ‘index.html’ saved [0]

[elcste]

@popey

• Why does the URL have a dot in it?

From http://www.dns-sd.org/trailingdotsindomainnames.html:

It’s a little-known fact, but fully-qualified (unambiguous) DNS domain names have a dot at the end. People running DNS servers usually know this (if you miss the trailing dots out, your DNS configuration is unlikely to work) but the general public usually doesn’t. A domain name that doesn’t have a dot at the end is not fully-qualified and is potentially ambiguous.

[seb128]

https://launchpad.net/bugs/1880258 has details on the dot question

[seb128]

I’ve reported a RT ticket to the IS team about that issue now

[conanth]

I have same issue after upgrading to Ubuntu desktop 22.10
I have to remove “.” after “com” or turn off Connectivity Checking in Settings

[phil-hughes]

I have been seeing the same thing recently on a desktop running 22.10. nmcli shows connection flipping between full and portal. However, my internet connectionn is not affected. Does not seem to happen on a box running 22.04.

me@desktop:~$ nmcli netw con
portal
me@desktop:~$ nmcli monitor
Networkmanager is now in the 'connected' state
Connectivity is now 'full'
Networkmanager is now in the 'connected (site only)' state
Connectivity is now 'portal'
Networkmanager is now in the 'connected' state
Connectivity is now 'full'
Networkmanager is now in the 'connected (site only)' state
Connectivity is now 'portal'
Networkmanager is now in the 'connected' state
Connectivity is now 'full'
Networkmanager is now in the 'connected (site only)' state
Connectivity is now 'portal'

[jbicha]

The Ubuntu 22.10 issue is being tracked at https://launchpad.net/bugs/1998082 and I opened another RT ticket for it.

[jbicha]

The RT ticket has been marked fixed and I can no longer duplicate the issue on Ubuntu 22.10.

[bernard010]

Awesome!!,
Thanks very much for the RT Ticket.