Solved Network unreachable, No route to host, phones disconnection

[gutenmorgenuhu]

Hi,
I have a problem concerning my 3CX installation which stops working some minutes after a reboot. The Activity log is full of these messages:

05/16/2022 8:16:11 PM - There's another STUN server that resolves to the same IP: 147.135.193.83:3478/UNKNOWN_TRANSPORT fk=0 tgt=; ignored

05/16/2022 7:56:11 PM - [CM306002]: There is no valid STUN server specified! External IP can not be resolved.

05/16/2022 7:36:11 PM - There's another STUN server that resolves to the same IP: 147.135.193.83:3478/UNKNOWN_TRANSPORT fk=0 tgt=; ignored

05/16/2022 7:35:39 PM - [CM101001]: Can not determine any local IP Address!

05/16/2022 7:35:38 PM - Failed to find best route to 2001:a60:1:8::10, error 101: Network is unreachable

05/16/2022 7:35:38 PM - Failed to find best route to 2001:a60:1:7::10, error 101: Network is unreachable

05/16/2022 7:35:38 PM - [CM504005]: Registration failed for: Lc:10001(@M-net Fax[<sip:[email protected]:0/TCP>]); Cause: Cause: 503 No route to host/REGISTER from local

05/16/2022 7:35:38 PM - [CM504005]: Registration failed for: Lc:10001(@M-net Fax[<sip:[email protected]:0/TCP>]); Cause: Cause: 503 No route to host/REGISTER from local

05/16/2022 7:32:41 PM - [CM504005]: Registration failed for: Lc:10000(@M-net[<sip:[email protected]:0/UDP>]); Cause: Cause: 503 No route to host/REGISTER from local

05/16/2022 7:32:38 PM - Failed to find best route to 2001:a60:1:8::10, error 101: Network is unreachable

05/16/2022 7:32:38 PM - Failed to find best route to 2001:a60:1:7::10, error 101: Network is unreachable

05/16/2022 7:32:38 PM - [CM504005]: Registration failed for: Lc:10002(@M-net Maya[<sip:[email protected]:0/TCP>]); Cause: Cause: 503 No route to host/REGISTER from local

05/16/2022 7:20:04 PM - [CM101001]: Can not determine any local IP Address!

05/16/2022 7:16:11 PM - [CM306002]: There is no valid STUN server specified! External IP can not be resolved.

05/16/2022 7:09:54 PM - Failed to find best route to 2001:a60:1:8::10, error 101: Network is unreachable

05/16/2022 7:09:54 PM - Failed to find best route to 2001:a60:1:7::10, error 101: Network is unreachable

05/16/2022 7:09:24 PM - [CM504005]: Registration failed for: Lc:10001(@M-net Fax[<sip:[email protected]:0/TCP>]); Cause: Cause: 503 No route to host/REGISTER from local

05/16/2022 6:56:11 PM - There's another STUN server that resolves to the same IP: 147.135.193.83:3478/UNKNOWN_TRANSPORT fk=0 tgt=; ignored

05/16/2022 6:36:11 PM - [CM306002]: There is no valid STUN server specified! External IP can not be resolved.

05/16/2022 6:33:58 PM - Failed to find best route to 2001:a60:1:7::10, error 101: Network is unreachable

05/16/2022 6:33:58 PM - [CM504005]: Registration failed for: Lc:10001(@M-net Fax[<sip:[email protected]:0/TCP>]); Cause: Cause: 503 No route to host/REGISTER from local

The firewall checker is completely green on all ports. Not a single fail. I a m behind a dynamic IP address.
I cannot understand these error messages because the machine running 3cx clearly gets an IP address:

 inet 192.168.10.229/24 brd 192.168.10.255 scope global dynamic ens3
       valid_lft 39sec preferred_lft 39sec
    inet6 fe80::11:32ff:fe2a:c105/64 scope link
       valid_lft forever preferred_lft forever

Can anyone point me in the right direction what is wrong here?

kind regards

 

[JohnS_3CX]

Hello,

Try disabling the IPv6 protocol on your NIC, and then restart the machine.

It appears to be looking for a path to the internet over IPv6 but fails:
05/16/2022 6:33:58 PM - Failed to find best route to 2001:a60:1:7::10, error 101: Network is unreachable

 

[gutenmorgenuhu]

Thank you for your suggestion. I tried that and disapbled ipv6 completely (see ifconfig in attachment)
But the errors still persist:

05/18/2022 9:51:50 PM - [CM101001]: Can not determine any local IP Address!
05/18/2022 9:51:50 PM - Failed to find any IP!
05/18/2022 9:46:01 PM - [CM306002]: There is no valid STUN server specified! External IP can not be resolved.
05/18/2022 9:31:57 PM - [CM504005]: Registration failed for: Lc:10000(@M-Net[<sip:[email protected]:0/TCP>]); Cause: Cause: 503 No route to host/REGISTER from local
05/18/2022 9:31:56 PM - [CM504005]: Registration failed for: Lc:10000(@M-Net[<sip:[email protected]:0/TCP>]); Cause: Cause: 503 No route to host/REGISTER from local
05/18/2022 9:31:56 PM - [CM504005]: Registration failed for: Lc:10000(@M-Net[<sip:[email protected]:0/UDP>]); Cause: Cause: 503 No route to host/REGISTER from local
05/18/2022 9:31:56 PM - [CM504005]: Registration failed for: Lc:10000(@M-Net[<sip:[email protected]:0/UDP>]); Cause: Cause: 503 No route to host/REGISTER from local
05/18/2022 9:28:55 PM - [CM101001]: Can not determine any local IP Address!
05/18/2022 9:28:55 PM - Failed to find any IP!
05/18/2022 9:26:01 PM - There's another STUN server that resolves to the same IP: 147.135.193.83:3478/UNKNOWN_TRANSPORT fk=0 tgt=; ignored

But the 3cx web view clearly states my (correct) public IP Adress and the stun servers are correctly set up and the ports are correctly forwarded (see attachments)

 

[gutenmorgenuhu]

So I made some progress here. I set my 3cx server into a DMZ and now the errors mostly disappeared but 2 persist:

05/19/2022 7:26:02 AM - There's another STUN server that resolves to the same IP: 147.135.193.83:3478/UNKNOWN_TRANSPORT fk=0 tgt=; ignored
05/19/2022 7:06:02 AM - [CM306002]: There is no valid STUN server specified! External IP can not be resolved.
05/19/2022 6:46:02 AM - There's another STUN server that resolves to the same IP: 147.135.193.83:3478/UNKNOWN_TRANSPORT fk=0 tgt=; ignored
05/19/2022 6:26:02 AM - [CM306002]: There is no valid STUN server specified! External IP can not be resolved.
05/19/2022 6:06:02 AM - There's another STUN server that resolves to the same IP: 147.135.193.83:3478/UNKNOWN_TRANSPORT fk=0 tgt=; ignored
05/19/2022 5:46:02 AM - [CM306002]: There is no valid STUN server specified! External IP can not be resolved.
05/19/2022 5:26:02 AM - There's another STUN server that resolves to the same IP: 147.135.193.83:3478/UNKNOWN_TRANSPORT fk=0 tgt=; ignored
05/19/2022 5:06:02 AM - [CM306002]: There is no valid STUN server specified! External IP can not be resolved.
05/19/2022 4:46:02 AM - There's another STUN server that resolves to the same IP: 147.135.193.83:3478/UNKNOWN_TRANSPORT fk=0 tgt=; ignored
05/19/2022 4:26:02 AM - [CM306002]: There is no valid STUN server specified! External IP can not be resolved.
05/19/2022 4:06:02 AM - There's another STUN server that resolves to the same IP: 147.135.193.83:3478/UNKNOWN_TRANSPORT fk=0 tgt=; ignored
05/19/2022 3:46:02 AM - [CM306002]: There is no valid STUN server specified! External IP can not be resolved.
05/19/2022 3:26:02 AM - There's another STUN server that resolves to the same IP: 147.135.193.83:3478/UNKNOWN_TRANSPORT fk=0 tgt=; ignored
05/19/2022 3:06:02 AM - [CM306002]: There is no valid STUN server specified! External IP can not be resolved.
05/19/2022 3:05:58 AM - [EC100009]: External application [3cx:0/PbxConfigTool] is disconnected:
05/19/2022 2:46:02 AM - There's another STUN server that resolves to the same IP: 147.135.193.83:3478/UNKNOWN_TRANSPORT fk=0 tgt=; ignored
05/19/2022 2:26:02 AM - [CM306002]: There is no valid STUN server specified! External IP can not be resolved.
05/19/2022 2:06:02 AM - There's another STUN server that resolves to the same IP: 147.135.193.83:3478/UNKNOWN_TRANSPORT fk=0 tgt=; ignored
05/19/2022 1:46:02 AM - [CM306002]: There is no valid STUN server specified! External IP can not be resolved.
05/19/2022 1:26:02 AM - There's another STUN server that resolves to the same IP: 147.135.193.83:3478/UNKNOWN_TRANSPORT fk=0 tgt=; ignored
05/19/2022 1:06:02 AM - [CM306002]: There is no valid STUN server specified! External IP can not be resolved.
05/19/2022 12:46:01 AM - There's another STUN server that resolves to the same IP: 147.135.193.83:3478/UNKNOWN_TRANSPORT fk=0 tgt=; ignored
05/19/2022 12:26:01 AM - [CM306002]: There is no valid STUN server specified! External IP can not be resolved.
05/19/2022 12:06:01 AM - There's another STUN server that resolves to the same IP: 147.135.193.83:3478/UNKNOWN_TRANSPORT fk=0 tgt=; ignored

Can I ignore that or does this need fixing ?

 

[JohnS_3CX]

Hi,

You can ignore this message, it is not a fault but it will appear when you are using Dynamic mode:

05/18/2022 9:26:01 PM - There's another STUN server that resolves to the same IP: 147.135.193.83:3478/UNKNOWN_TRANSPORT fk=0 tgt=; ignored

Is it working normally now that you put it in the DMZ?

If yes, then you can be almost sure that your firewall was blocking you.

 

[gutenmorgenuhu]

I think it is working now. I get log spammed by this:

05/21/2022 11:46:07 AM - [CM306002]: There is no valid STUN server specified! External IP can not be resolved.
05/21/2022 11:06:07 AM - [CM306002]: There is no valid STUN server specified! External IP can not be resolved.
05/21/2022 10:26:07 AM - [CM306002]: There is no valid STUN server specified! External IP can not be resolved.
05/21/2022 9:46:07 AM - [CM306002]: There is no valid STUN server specified! External IP can not be resolved.

but my correct IP is shown under Dashboard -> Information

I was able to militarize the DMZ again. Maybe for future reference :

The problem was that my 3cx instance was in my IoT VLAN. The wall did not allow any connections from devices to the gateway, so there was actually truth to 3cx logs stating that there is no route to host because it couldn't even reach the first HOP.
That was partly to my misunderstanding of the wall rules of my Ubiquiti DMP. I had to specify a wall rule for "LAN local" instead of LAN in.

I still wonder why a newly rebooted 3cx instance worked for some hours tho but at least I got it working now.

 

[NickD_3CX]

Glad to hear you got it working, but that is indeed strange.

Anyhow, I will mark this thread as 'Solved'.