after the update described above I have problems with the wifi calling service from Vodafone and an IPhone7.
the udp connection via port 4500 is not established. Nothing is shown in the firewall log for this connection either. The firewall does not block anything according to the policy.
This error exists only since the update. Firewall, switch and DSL modem have all been updated and restarted.
in other networks wifi calling works fine.
Anyone have any idea what the hell is going on ?
I wonder what the output of a ping flood between your ipfire and your isp assigned default gateway for half an hour would output? with you using your phone during the test?
Does it print more than 4 dots and not scale back to one? ping -f -t 2 the-ip-of-your-ISP-gateway
If it does one thing to try would be backup your settings and do a fresh install of ipfire, but call your isp’s technical Support center and ask them to reprovision your modem before you reconnect the new IP fire installation with the settings from the backup file.
I realize the above solution might solve the problem, but it’s kind of fishy that your DNS isn’t working and I suspect that somebody may be deleting the DNS pointer to a malicious activity on the internet, and it would have broken routes with your ISP’s DNS settings and that’s something that has to be fixed on your ISP side by reprovisioning your modem. This problem commonly happens when your connection is being botnetted.
But then again it could just be a glitch with the DNS program. You won’t know until you try it.