Could not connect to packages.openmediavault.org:80

Hello,

I have an old arrakis install.

Running apt-get update, I get:

Err:16 http://packages.openmediavault.org/public arrakis InRelease
  Es konnte keine Verbindung zu package.openmediavault.org:80 (178.254.11.33) hergestellt werden, Zeitüberschreitung der Verbindung

[Timeout, that is]

When I ping 178.254.11.33, I get no reply on my omv machine. If I ping the same from another machine in the same network, I do get a reply. Also note, that there was no issue getting the data from other servers (https://openmediavault-plugin-developers.github.io for instance).

What could be the reason for this partial network problem?

Best regards,

Hendrik