Urgent Support help - SIP Trunk issue

[pa_an_br]

Hi

Out of the blue, we are now having issues with calls when dialling out.

Pcap shows 3CX is not replying to the invite packets being sent by Gamma.

This only started happening today with no changes to the our FW amd no updates installed on 3CX either.

No issues, with incoming that we can tell, testing working as it should.

Thanks in advance.

 

[Alphabetic]

Have you asked Gamma?

Have you done a firewall test?

Have you had a new router?

 

[Guillaume Bourgeois]

Hi

Out of the blue, we are now having issues with calls when dialling out.

Pcap shows 3CX is not replying to the invite packets being sent by Gamma.

This only started happening today with no changes to the our FW amd no updates installed on 3CX either.

No issues, with incoming that we can tell, testing working as it should.

Thanks in advance.

You said ;

when dialling out

and said :

3CX is not replying to the invite packets

That seems contradictory to me...
For outgoing calls, it’s 3CX that sends the INVITEs, not the other way around.

 

[pa_an_br]

Hi

Yes, first call was to Gamma, firewall test is clear.

Nothing on the network has changed in the more than 3mths. Apologies looks like invites incoming, we have numbers on another system that come over a different trunk.

Call or reg to : 07xxxxxxxxx 10002@Gamma (3CX SIP Port 5060 required)) has failed. 0.0.0.0 replied: 408 Request Timeout; internal

That was an outgoing call.

This what Gamma have sent us:

Source is them, destination is our external IP.

 

[pa_an_br]

Apologies for the delay in reply, im currently on holiday trying to support the guys in the office lol

 

[Guillaume Bourgeois]

Hi

Yes, first call was to Gamma, firewall test is clear.

Nothing on the network has changed in the more than 3mths. Apologies looks like invites incoming, we have numbers on another system that come over a different trunk.

Call or reg to : 07xxxxxxxxx 10002@Gamma (3CX SIP Port 5060 required)) has failed. 0.0.0.0 replied: 408 Request Timeout; internal

That was an outgoing call.

This what Gamma have sent us:
View attachment 43265
Source is them, destination is our external IP.

Send me your PCAP privately, and I'll analyze it further.

FYI ;
It’s a bit like saying that when a visitor arrives at your front door, you’re the one signaling (with a doorbell) to let them know they’ve arrived, rather than the visitor doing it. This doesn’t make sense.

For an outbound call initiated by a user from 3CX, it’s 3CX that sends the call to your provider,
Gamma, not the other way around.
How could Gamma know that your user wants to make an outbound call if 3CX isn’t sending the details to Gamma?

 

[pa_an_br]

Send me your PCAP privately, and I'll analyze it further.

FYI ;
It’s a bit like saying that when a visitor arrives at your front door, you’re the one signaling (with a doorbell) to let them know they’ve arrived, rather than the visitor doing it. This doesn’t make sense.

For an outbound call initiated by a user from 3CX, it’s 3CX that sends the call to your provider,
Gamma, not the other way around.
How could Gamma know that your user wants to make an outbound call if 3CX isn’t sending the details to Gamma?

I dont have anymore than what they sent me, sorry. Ive replied to the ticket to them for more info.

Just had an update from site to say incoming isnt working aswell now. Just logging on to see the errors if any.

Thanks

 

[Guillaume Bourgeois]

No issues, with incoming that we can tell, testing working as it should.

Just had an update from site to say incoming isnt working aswell now. Just logging on to see the errors if any.

So, it’s an issue with incoming calls, meaning calls directed to 3CX?
Once Gamma has resolved the issue, if it persists, please obtain a capture and send it to me privately, and I’ll assist you.

Best regards,

 

[pa_an_br]

One of the other techs just spotted it in the Blocklist. But the error didn't didn't say blocked as I've seen before.

Thanks for the help though, much appreciated!