stun.3cx.com - Are there updated DNS entries for 3CX subnets ?!?

[serv-u Franzke]

Dear 3CX,

I'd like to come back to an old forum post from late 2019 (https://www.3cx.com/community/threads/firewall-tests-stun-eu-3cx-com-and-51-91-201-8x.68865/). In this post @YiannisH_3CX states that the DNS settings might be updated. Anyhow, they weren't updated so far. Do you have any news an this? Just like @Haxoy we'd like to add all relevant FQDN, e.g. stun.3cx.com, to our customers' firewalls but if they don't resolve properly we have to manually search and later add all the necessary entries. And to be blunt: this sucks!!
Could anyone from 3CX please confirm that the following IP addresses are stil correct? Especially 51.91.201.86 seems to play an important role within the 3CX firewall check

51.38.45.26 stun.3cx.com
51.91.201.86 stun.3cx.com

54.39.182.217 stun2.3cx.com
51.79.116.90 stun2.3cx.com

54.37.20.144 stun3.3cx.com
151.80.120.125 stun3.3cx.com

54.39.188.150 stun4.3cx.com
54.39.75.88 stun4.3cx.com

On top of this querying stun.3cx.com leads to:

54.39.179.240
54.39.188.188
147.135.193.83
207.246.124.251
54.38.41.146

Is there any chance to get a full list or proper DNS settings?

Best regards and thank you in advance!

Thorsten

​

 

[cpe90]

Watching...

 

[SteveITS]

I suspect the "problem" with publishing a list, is that some people will open the ports for those IPs, pass the test, and tell 3CX support the firewall test passes, when in fact they have ports closed for apps, remote audio, SIP, etc. If the goal is to have the test show it passed on the dashboard, one can open all the ports, run the test, and restrict the ports again. Plus 3CX can move servers/IPs at will without a list.

Some firewalls will resolve FQDNs in aliases or rules...pfSense will.

 

[cpe90]

Question for a newbie.

According to https://www.3cx.com/docs/manual/firewall-router-configuration/
that using STUN is not recommended.

But then I still could see stun traffic on my PALO FW when running a firewall test in the 3CX dashboard.
Can I safely ignore it then?

Thanks!!

 

[jed]

But then I still could see stun traffic on my PALO FW when running a firewall test in the 3CX dashboard.
Can I safely ignore it then?

You can safely ignore it. The Firewall test actually uses the 3CX STUN Servers to test the Firewall