Webchat WebSocket 502 on BYOC Trunk Integration

Looking for advice on handling WebSocket 502 errors when routing digital sessions through our Singapore BYOC trunks.

We have configured a custom integration to map incoming webchat sessions to specific SIP trunks for CTI popup purposes, but the connection drops immediately upon session creation. The Architect flow shows a successful ‘Start Conversation’ action, yet the frontend receives a 502 Bad Gateway from the websocket endpoint. This happens specifically on trunks registered in the Asia/Singapore region, while our US trunks function normally. We are using the latest Genesys Cloud Web Chat SDK and have verified that the trunk registration status is active with no SIP errors in the logs. The issue appears to be related to how the platform handles the bridge between the digital channel and the telephony trunk metadata, causing the websocket to terminate before the first message is exchanged. Any insights into the correct configuration for exposing trunk data to digital sessions without triggering gateway timeouts?

The problem is likely that related to how the WebSocket handshake is being terminated before the recording context is fully established, rather than the BYOC trunk itself. When mapping digital sessions to SIP for CTI, the system often struggles to maintain the session state if the trunk registration lacks proper keep-alive intervals. For legal discovery purposes, this drop causes a gap in the metadata chain of custody. Try adding a small delay in your Architect flow after the ‘Start Conversation’ action to allow the WebSocket to stabilize before triggering the trunk lookup. Additionally, verify that the S3 bucket permissions allow for immediate write access to the session metadata, as a 502 can sometimes be a proxy error masking a backend storage failure. Ensure the OAuth token used for the trunk integration has ‘recording:read’ and ‘recording:write’ scopes explicitly defined, not just inherited from a broader role.