Hi, I face the following issue. My BYOC SIP's stop working after few days of working fine. It repeats probably once a week (I have to check it thoroughly). It looks as if from some reason the session expired. It helps to remove SIP's from integrations pane and then add them again and after that import phone numbers once again. Please check it as it prevents from using Vapi in prod env.

The issue appears to be related to SIP trunk session management. Here are the steps to diagnose and resolve the issue: 1. Verify Network Configuration: - Ensure Vapi's SIP server static IPs are whitelisted: - 44.229.228.186 - 44.238.177.138 2. Check SIP Trunk Configuration: - Verify your SIP endpoint configuration is correct - Ensure destination formats match SIP addressing requirements - Check for conflicting call control settings 3. Session Management: - Your current workaround of removing and re-adding SIP trunks suggests a session timeout issue - Review your SIP provider's session timeout settings - Check if your provider requires periodic session refresh/keepalive 4. Packet Analysis: When the issue occurs, you can use Wireshark to analyze SIP signaling by: - Downloading the PCAP file from the API - Filtering for SIP packets using "sip.Method == "REFER"" - Looking for session termination messages or timeouts For a permanent fix, I recommend: 1. Reviewing your SIP provider's session timeout configuration 2. Implementing proper session refresh mechanisms if required 3. Working with your SIP provider to ensure proper session persistence Let me know if you need help implementing any of these specific solutions or would like to investigate further diagnostic steps.

Hi, thank you for your suggestions. However I doubt the issue comes from the SIP provider. I have 10 SIP accounts from this provider and from those only 2 connected to Vapi have issues. Wireshark is not helpful here because when the issue occurs, there is no traffic from your IP addresses at the provider side. By the way why do you suggest filtering REFER? I would recommend filtering SIP REGISTER at your side for the IP provided in my configuration. This would perhaps explain why you stop sensing SIP REGISTER messages. Yes, you are correct, the SIP session requires refreshing by repetitive sending of SIP REGISTER. How often? Its decided by the SIP parameter: expires.

Hey there, We completely understand your doubts regarding the SIP provider, especially since the problem only affects the two SIP accounts connected to Vapi, while the other accounts with the same provider work without issue we reviewed the details of your request and brought this to our team's attention. We will be getting back to you as soon as we can. Thank you for your continued patience!

please let me know whats the result of your team's action. The problem keeps occurring

We’ll look into this further on our side. In the meantime, if you’re able to share any PCAP files from when the issue occurs, we can analyze those as well to help narrow down the root cause.