Hello Folks,
We have an issue with calls that are following below call path:
ITSP >> SIP >> CUBE >> SIP >> CLOUD Contact Center SIP Server
** Note: we have a firewall between the CUBE and Cloud that is making the natting for L3 only.
the issue happens randomly with some calls not all but its furustrating the customers that are reaching the agents.
I did some basic troubleshooting and found that the call initiated successfully in both working and non-working scenarios but the difference between working and non-working calls is that the non-working call scenarion the gateway is sending sip options messages after the call get established and we recieve no response from the Cloud. gateway send 7 sip options then the sends a bye message with Q850 127 reason code. when we checked the packet capture on the Cloud sip server we found the UDP sip messages arrives to the Cloud sip server with UDP port number, but the options sip message arrives with a different UDP port number. and the Cloud SIP server response to the SIP options with Invite source port not the with the sip options UDP port. and hence looks like the 200OK on the sip options is not reaching the CUBE. from the CUBE the source port will be 5060 always. so I am expecting that it has something to do with the SIP ALG on the firewall or the cloud server is behaving uncorrectly.
My question is there any way to disable options message to be sent during the call? Please note that i am not asking about options-ping or keepalive. or is there any relation between those and the calls sip options that is sent with the same call-id as the initiated calls?
please find below the bye that is sent by the CUBE:
Sent:
BYE sip:8668445@x.x.x.x:4004 SIP/2.0
Via: SIP/2.0/UDP 192.168.100.50:5060;branch=z9hG4bK30A2087C3
From: <sip:0541636818@192.168.100.50>;tag=E7C76FE1-9FB
To: <sip:8668445@x.x.x.x>;tag=11810747492970300
Date: Wed, 14 Feb 2024 13:53:09 GMT
Call-ID: E64E875E-CA5D11EE-9FECFDEF-8BD26FCD@192.168.100.50
User-Agent: Cisco-SIPGateway/IOS-15.5.3.S4b
Max-Forwards: 70
Timestamp: 1707907994
CSeq: 103 BYE
Reason: Q.850;cause=127
Content-Length: 0
below is the options sip message that was sent to the cloud sip server:
Sent:
OPTIONS sip:8668445@x.x.x.x:4004 SIP/2.0
Via: SIP/2.0/UDP 192.168.100.50:5060;branch=z9hG4bK30A207825
From: <sip:0541636818@192.168.100.50>;tag=E7C76FE1-9FB
To: <sip:8668445@x.x.x.x>;tag=11810747492970300
Date: Wed, 14 Feb 2024 13:53:09 GMT
Call-ID: E64E875E-CA5D11EE-9FECFDEF-8BD26FCD@192.168.100.50
User-Agent: Cisco-SIPGateway/IOS-15.5.3.S4b
Max-Forwards: 70
CSeq: 102 OPTIONS
Contact: <sip:0541636818@192.168.100.50:5060>
Content-Length: 0
Also I would appreciate is someone can explain why this options sip message is sent during the call? Is it to check the status of the call?
Thanks in advance.
