No idea why this is happening, the WebSocket connections to our Genesys Cloud Edge instance drop unexpectedly when we simulate a moderate load of 50 concurrent agents. We are running a proof-of-concept for our Singapore office to validate the BYOC setup before full migration. The goal is to ensure the local Edge can handle the initial burst of agent logins without falling back to the public cloud, which adds unacceptable latency.
We are using JMeter 5.4.1 to simulate the agent login sequence. The script performs the standard OAuth token exchange and then initiates the WebSocket connection to the Edge endpoint. For the first 20-30 connections, everything works perfectly. The agents register, and the heartbeat is stable. However, once we hit around 35-40 concurrent threads, the WebSocket handshakes start failing. We see a mix of 502 Bad Gateway and 408 Request Timeout errors in the JMeter response messages.
Here is the environment setup:
- Genesys Cloud Edge Version: 2.1.0
- JMeter Version: 5.4.1
- Thread Count: 50 (Ramp-up: 5 seconds)
- Locale: Asia/Singapore
- Edge Node Status: Healthy (all services green in the Edge dashboard)
We have checked the Edge logs and do not see any obvious resource exhaustion errors like OOM or CPU spikes. The network latency between the load generator and the Edge node is under 5ms, so that is not the bottleneck. We also verified that the API rate limits are not being hit, as the WebSocket connection is a separate protocol from the REST API calls.
Is there a default connection limit on the Edge BYOC WebSocket endpoint that we are unaware of? Or is there a specific configuration in the Edge deployment YAML that needs to be tuned for higher concurrency? We want to avoid opening a support ticket if this is a known configuration issue. Any pointers on where to look next would be appreciated.
Make sure you verify the WebSocket keep-alive intervals are not exceeding the Edge timeout threshold during the burst.
"keepAliveInterval": 15000,
"maxRetries": 3
Adjusting this usually prevents the premature disconnects seen in high-concurrency tests.
You need to adjust the keep-alive settings to match the Edge timeout.
- Set
"keepAliveInterval": 15000
- Set
"maxRetries": 3
This prevents premature drops during the burst.
Ah, yeah, this is a known issue…
The WebSocket instability during the initial agent login burst is rarely a pure network fault. It is typically a resource contention problem within the Edge instance itself. When 50 agents log in simultaneously, the Edge must process authentication tokens, register devices, and establish media paths. If the keep-alive interval is too aggressive, the Edge may drop connections to preserve resources for the active signaling load.
The suggestion above regarding the 15-second interval is a good starting point, but consider increasing the maxRetries to 5. This provides a larger buffer for the Edge to stabilize under the burst. Additionally, verify that the JMeter script is not closing connections prematurely. The Edge expects a steady stream of keep-alive pings. If the test tool sends them too frequently, the Edge may interpret this as abnormal behavior and terminate the session. Adjust the payload to match the standard WebRTC signaling protocol. This usually resolves the disconnects without requiring infrastructure changes.
You need to look beyond the keep-alive settings and inspect the actual authentication payload size during the burst. The 403 errors and subsequent disconnects often stem from the Edge ingress layer dropping connections when it encounters a spike in concurrent token validation requests that exceed the default rate limit for BYOC instances.
The documentation indicates that strict token validation at the ingress layer is sensitive to these spikes. If your JMeter script sends the full JWT in the header for every reconnection attempt without caching, you are hitting the rate limiter. This causes the Edge to reject the connection before the WebSocket handshake completes.
To fix this, ensure your load test script implements token caching. Do not re-authenticate every time a connection drops. Instead, reuse the valid token until it expires. This reduces the load on the ingress layer significantly.
Also, check your S3 bucket policies. If you are logging these connection attempts for audit trails, ensure the bucket allows large objects and that the KMS encryption context is preserved. A blocked write to the audit log can sometimes cause a cascade failure in the connection state.
Here is a quick check for your JMeter setup:
{
"authStrategy": "cache_token",
"tokenRefreshThreshold": 90,
"maxConcurrentAuthRequests": 5
}
This configuration ensures that only 5 concurrent auth requests are sent at any time, while the rest wait for a cached token. This aligns with the best practices for Edge BYOC authentication.
For more details on handling authentication spikes in BYOC environments, refer to this support article: https://support.genesys.cloud/articles/byoc-auth-spike-handling
This usually resolves the disconnects seen during moderate load tests. If the issue persists, check the Edge logs for any resource contention warnings. The system might be throttling connections to preserve resources for active signaling.