Incoming and Outgoing calls intermittently not connecting

[danlay]

Recently upgraded and changed SIP provider to Gamma.
Dialling numbers intermittently connects, i.e. you could dial an external number 4 times and only connect on the 4th attempt.

There is no ringing tone, the line simply goes dead and does not connect speech path.

Customers have reported problems calling in so I assume that's the same issue.

Searching the forum it's very similar to this post, but there is no resolution in the comments.
Its interesting that the below case is also Gamma so could it be related with the sip trunk somehow?
https://www.3cx.com/community/threads/incoming-calls-not-connecting.70575/

I have spoken with the trunk provider and they've checked the logs, in all cases they've said that everything looks fine.

3CX Version: 18.0 Update 2 (Build 314)
Server OS: Windows Server 2019, VM
Is the 3CX Server Hosted and where: On-premises
IP Phone Make/Model/Firmware version: Yealink SIP-T48S Fw. 66.86.0.5
Provisioning Method: Local
Trunk Provider: Gamma
Has the Firewall Checker passed: YES
Are custom Phone Templates being used: NO

 

[ChrisC_3CX]

I have spoken with the trunk provider and they've checked the logs, in all cases they've said that everything looks fine.

Did they provide additional info about this? For instance, if they checked a case where outgoing calls didn't work, did they confirm that they saw the calls reaching them and then confirmed that they sent them onwards? If yes, it means that 3CX is already not in control of the call as it successfully sent it to the SIP Provider (in this case Gamma) who then routed it onwards.

Since it sounds like it's something you can replicate quite often, can you try this:
1. Go into "Dashboard >> Activity Log >> Settings" and enable Verbose Logging.
2. Make an outgoing call and confirm you reproduced the issue.
3. Check the Dashboard >> Event Log, do you see an error or warning? If yes what does it say?
4. If not, go into "Dashboard >> Activity Log", use the "Filter" button to only view the last call and go through the logs a bit, do you see any errors or something that seems off?

Note: Should you copy any logs here please make sure to obfuscate any sensitive data such as FQDN, your public ip, phone numbers, etc.

 

[danlay]

Hi ChrisC thanks for your quick response.

The response from the Gamma reseller is as follows:

"When speaking to the network about the issues you were experiencing, they advised the calls are terminating correctly as the signals required to close the call are being received. This means the call is ending and not being cut off.
I have completed a check on the SIP service and as the network confirm there are no issues with the service, I would have to advise you speak to the hardware provider."

I enabled Verbose logging as you mentioned and there's some 503 errors in there:

11/02/2022 13:35:02 - L:1.1[Extn:101] Sending: OnSendResp Send 500/INVITE from 0.0.0.0:0 tid=1624177765 [email protected]:

SIP/2.0 500 Server Internal Error

Via: SIP/2.0/UDP 192.168.7.73:5060;branch=z9hG4bK1624177765

To: <sip:[email protected]:5060>;tag=9a77626d

From: "User Name"<sip:[email protected]:5060>;tag=1623987953

Call-ID: [email protected]

CSeq: 2 INVITE

Warning: 499 VOIP02.company.internal "Server Failure"

Content-Length: 0



11/02/2022 13:35:02 - SendMsg from <sip:[email protected]:5060>;tag=9a77626d to "User Name"<sip:[email protected]:5060>;tag=1623987953

11/02/2022 13:35:02 - Call(C:1) is terminated

11/02/2022 13:35:02 - [CM503020]: Call(C:1): Normal call termination. Call originator: Extn:101. Reason: Server Failure

11/02/2022 13:35:02 - [CM503016]: Call(C:1): Attempt to reach <sip:[email protected]:5060> from Extn:101 has failed. Reason: Server Failure

11/02/2022 13:35:02 - [Flow] Current call diversion path:[]

11/02/2022 13:35:02 - L:1.1[Extn:101] failed to reach Line:10000>>03302005103, reason Server Failure

11/02/2022 13:35:02 - RerouteReq

11/02/2022 13:35:02 - Leg L:1.2[Line:10000>>03302005103] is terminated: Cause: 503 Service Unavailable/INVITE from 88.215.60.77:5060

11/02/2022 13:35:02 - L:1.2[Line:10000>>03302005103] got Terminated Recv 503/INVITE from 88.215.60.77:5060 tid=e1716032d634112e Call-ID=KfT57_IWqTCpzaRCwhgdXg..:

SIP/2.0 503 Service Unavailable

Via: SIP/2.0/UDP **WANIP**:5060;rport=5060;received=**WANIP**;branch=z9hG4bK-524287-1---e1716032d634112e

Contact: <sip:[email protected]:5060>

To: <sip:[email protected]>;tag=3853575302-242447481

From: <sip:0845*******@88.215.60.77>;tag=6e2c4c1f

Call-ID: KfT57_IWqTCpzaRCwhgdXg..

CSeq: 1 INVITE

Allow: UPDATE, PRACK, INFO, NOTIFY, OPTIONS, BYE, INVITE, ACK, CANCEL

Reason: Q.850;cause=41;text="Temporary failure"

Content-Length: 0



11/02/2022 13:35:02 - Terminated from <sip:[email protected]>;tag=3853575302-242447481 to <sip:0845*******@88.215.60.77>;tag=6e2c4c1f; reason: Error

11/02/2022 13:35:02 - Call to T:Line:10000>>03302005103@[Dev:sip:[email protected]:5060] from L:1.1[Extn:101] failed, cause: Cause: 503 Service Unavailable/INVITE from 88.215.60.77:5060

11/02/2022 13:35:02 - L:1.2[Line:10000>>03302005103] got Failure: Failure Recv 503/INVITE from 88.215.60.77:5060 tid=e1716032d634112e Call-ID=KfT57_IWqTCpzaRCwhgdXg..:

SIP/2.0 503 Service Unavailable

Via: SIP/2.0/UDP **WANIP**:5060;rport=5060;received=**WANIP**;branch=z9hG4bK-524287-1---e1716032d634112e

Contact: <sip:[email protected]:5060>

To: <sip:[email protected]>;tag=3853575302-242447481

From: <sip:0845*******@88.215.60.77>;tag=6e2c4c1f

Call-ID: KfT57_IWqTCpzaRCwhgdXg..

CSeq: 1 INVITE

Allow: UPDATE, PRACK, INFO, NOTIFY, OPTIONS, BYE, INVITE, ACK, CANCEL

Reason: Q.850;cause=41;text="Temporary failure"

Content-Length: 0



11/02/2022 13:35:02 - [CM503003]: Call(C:1): Call to <sip:[email protected]:0> has failed; Cause: 503 Service Unavailable/INVITE from 88.215.60.77:5060

11/02/2022 13:35:02 - Session 166 has failed in leg L:1.2[Line:10000>>03302005103] ; Cause: 503 Service Unavailable/INVITE from 88.215.60.77:5060

11/02/2022 13:35:02 - Failure from <sip:[email protected]>;tag=3853575302-242447481 to <sip:0845*******@88.215.60.77>;tag=6e2c4c1f

Let me know your thoughts..

Thanks
Dan

 

[danlay]

Update: please hold off on the response, I've just found out that the dialled number used to test may be out of service today!

 

[ChrisC_3CX]

Understood! Let us know what happens!