How to troubleshoot: "This server has no working Internet connection" error message

Hello Nextcloud specialists

Could somebody help me troubleshooting the following problem:
Error message in admin menu under “security & setup warnings”:
"This server has no working Internet connection"

What does Nextcloud check with that step?
Where could I find troubleshooting logs?
What to check?

I have a working internet connectivity. I can access the server via SSH and ping, curl and telnet to different websites directly from the shell. I’ve found several suggestions on the internet (like check DNS, check firewall, a.s.o. ) and I tried everything but I had no success.
In the nextcloud.log there’s no information.

To send e-mail from Nextcloud is also not possible. I don’t even see a connection attempt/request on my firewall when I push the “test e-mail settings” button. But again: When I log on to the server via SSH I can establish a connection to the SMTP server without any issues.

And also I can’t see the appstore I only can activate/deactivate preinstalled apps.

This error(s) appears from the beginning since I’ve installed NC via “dnf install” on Fedora 27. Means: It never worked before on that server.

Nextcloud version: 13.0.2
Operating system and version: Fedora 27
Apache or nginx version: Apache 2.4.33
PHP version: 7.1.17

update: Problem exists with NC 11, 12 and 13 as well (updated to 13.0.2 currently)

I have this issue as well. Running NC v13.0.1 and the system fails to connect to the update servers, does not show or allow app installs. Where in the TUI or Web UI do you configure this?

I started getting this error locking down php in php.ini by adding changing
disable_functions =
disable_functions = shell_exec,system,passthru,exec,curl_exec,proc_open,parse_ini_file,popen,eval,show_source,highlight_file

I am still trying to sort out disabling which command/s causes the error.
It’s lame that it’s assumed we run NextCloud with an insecured PHP


In fact I love clipping Nextcloud from communicating around the internet.
I need to make a note to my self to comment out the disable functions code to allow nextcloud to properly update it’s self…

This project really needs some security minded people, security is not trumped by functionality kids! never ever.