So I’m seeing a very odd bug with WebSocket handshake failures (1006) when simulating 500 concurrent agents via JMeter against our BYOC Edge deployment. The Genesys Cloud WebSocket SDK v2.4.1 drops connections immediately after the initial 201 response during peak throughput bursts. The Edge logs show no errors, but the client-side thread group reports a 40% drop in active connections. Is there a known capacity limit for WebSocket persistence on the BYOC Edge gateway that triggers this specific disconnect pattern under heavy load?
The main issue here is that the 1006 code indicates a clean close without a proper closing handshake, which in high-concurrency BYOC Edge scenarios usually points to upstream load balancer timeout misconfiguration rather than Genesys Cloud internal capacity limits. The Edge gateway itself can handle thousands of concurrent WebSocket connections, but the reverse proxy or hardware load balancer sitting in front of it often has aggressive idle timeout settings that terminate connections before the initial keep-alive heartbeat is exchanged. You need to verify that your load balancer is configured to allow long-lived TCP connections and that the WebSocket upgrade headers are being passed correctly through the entire chain. Specifically, check if the Sec-WebSocket-Protocol and Sec-WebSocket-Accept headers are being preserved during the upgrade process. If you are using NGINX as a reverse proxy, ensure your configuration includes the following directives to prevent premature connection termination: proxy_set_header Upgrade $http_upgrade; proxy_set_header Connection "upgrade"; proxy_read_timeout 86400; proxy_send_timeout 86400;. Additionally, the Genesys Cloud WebSocket SDK v2.4.1 has a known issue with reconnection logic when multiple threads attempt to reconnect simultaneously, causing a thundering herd effect that overwhelms the Edge gateway’s connection acceptance queue. Implementing an exponential backoff with jitter in your JMeter thread group can mitigate this. Set the initial retry delay to 100ms and increase it exponentially up to 5 seconds. This allows the Edge gateway to process the backlog of connections without dropping them due to resource exhaustion. Cross-referencing the Genesys Cloud API documentation for WebSocket specifications, the recommended approach is to handle the 1006 code gracefully by implementing a client-side retry mechanism with randomized delays. This ensures that the connections are re-established in a staggered manner, preventing the load balancer from hitting its connection limits again.
The docs actually state that WebSocket persistence is heavily influenced by the SIP registration state of the underlying BYOC trunks, not just the Edge gateway capacity. When managing multiple regional trunks, carrier-specific keep-alive intervals often conflict with the default Genesys Cloud heartbeat settings. This mismatch causes the upstream provider to drop the connection silently, resulting in the 1006 error you are seeing.
To fix this, verify the Transport settings in your outbound routing rules. Ensure the SIP credentials are configured to use TCP or TLS rather than UDP for the WebSocket bridge, as UDP lacks the necessary flow control for high-concurrency bursts. Additionally, check the Keep-Alive timer in the Edge configuration. If it is set to the default 30 seconds, increase it to 60 seconds to align with typical carrier timeouts in the APAC region. This adjustment usually stabilizes the handshake phase during load spikes.