ACK is not received

[Ash]

Hi,

I have been trying to find a way to fix my 3cx installation. All outgoing calls drop in 32 seconds.

Its hosted in AWS, Firewall checks are fine.
12/20/2018 7:23:17 PM - [CM503021]: Call(C:2): ACK is not received from sip:[email protected];transport=TCP

• resolving 'stun-au.3cx.com'... done
• resolving 'stun2.3cx.com'... done
• resolving 'stun3.3cx.com'... done
• resolving 'sip-alg-detector.3cx.com'... done
• testing 3CX SIP Server... done
  • stopping service... done
  • detecting SIP ALG... not detected
  • testing port 5060... done
  • starting service... done
• testing 3CX Tunneling Proxy... done
  • stopping service... done
  • testing port 5090... done
  • starting service... done
• testing 3CX Media Server... done
  • stopping service... done
  • testing ports [9000..9398]... done
    • testing port 9000... done
    • testing port 9002... done
    • testing port 9004... done
    • testing port 9006... done
    • testing port 9396... done
    • testing port 9398... done
  • testing ports [10600..10998]... done
    • testing port 10600... done
    • testing port 10602... done
    • testing port 10604... done
    • testing port 10994... done
    • testing port 10996... done
    • testing port 10998... done
  • starting service... done

Can anyone please help me to fix this issue.

thanks

 

[eddv123]

calls drop in 32 seconds

I have to say this despite what you have said above and the results of your FW checker, but 32 second drops are (in my opinion) 99% going to be Firewall related. I have however placed some similar strings below which suggest some of the other things you can look at:

https://www.3cx.com/community/threads/32-seconds-call-drops.46873/
https://www.3cx.com/community/threads/call-drops-after-30-32-sec.1663/

The only thing I would ask in regards to the dropped calls is have you tried testing to another external connection/number ? A trace and logging would also be of use.

 

[Ash]

Thanks for your reply. let me check the links. I have checked the ports again still the same isue

Open ports (incoming)
UDP : 9000 - 10999
TCP/UDP : 5090
TCP/UDP 5060 - 5061

outgoing
All Traffic.

 

[eddv123]

To make it official: https://www.3cx.com/docs/ports/

In my own experience however it has always been a SIP ALG related issue or perhaps as some of the strings suggest anti-virus software.

Your SIP ALG seems to pass OK however so it may not be this, again a trace or logging would be a good way of detecting this.

Note: Some firewall/routers do not have a GUI based tick box for disabling SIP ALG and it is often a CLI command that needs to be configured in the device.

 

[Ash]

This is a AWS server

 

[Ash]

Anyone ??

 

[eddv123]

Run a PCAP from 3CX (it can be done from the interface) and logging and send over via dropbox or something like that:

https://www.3cx.com/docs/capture-network-traffic/
https://www.3cx.com/docs/collecting-logs-for-3cx-support/

 

[NickD_3CX]

Another reason why the call may be dropping after 32 seconds due to "ACK not received" could be that although the ports are open, your 3CX is "telling" the provider/phones the wrong public IP, so they may be sending the ACK, just not to the correct IP.

I would suggest checking:

• Settings --> Network --> Public IP tab
  If you have a Static Public IP on your AWS, make sure "Static Public IP" is selected and that the correct IP is there.
  If your AWS does not have a Static Public IP, then you could set here "Dynamic Public IP".
  
  
• SIP Trunks --> edit your SIP Trunk --> Options tab
  In the "Select which IP to use in 'Contact' (SIP) and 'Connection'(SDP) fields" drop-down, usually you should have "Use Default Settings" selected.
  If you have "Put Public IP in SIP VIA Header" checked, also check if that IP is correct. DO NOT ENABLE THIS OPTION if you currently don't have it on. Most providers don't need it.