I’m completely stumped as to why our BYOC trunks in apac-1 are dropping calls with SIP 408 Request Timeout right after the 8am SG peak hits. we have 15 trunks configured with standard failover logic but the load balancer seems to ignore the primary carrier health checks until the timeout triggers. using SDK 2.4.1 and the latest Genesys Cloud API endpoints for trunk management, the status returns active even when the carrier is clearly throttling. this is causing significant latency in our analytics reporting pipeline since the call data is delayed by the retry logic. any insights on how to force a faster failover without changing the carrier settings directly?
I typically get around this by decoupling the health check frequency from the standard polling interval. The issue isn’t that the load balancer ignores the checks, but that the default 30-second interval is too slow for high-volume APAC peaks. By the time the 408 timeout triggers, the primary carrier has already queued thousands of calls that will fail.
For legal discovery and chain of custody, we need to ensure the metadata captures the reason for the failover, not just the result. If you rely on the default SIP 408, the recording metadata might lack the specific trunk health status at the moment of failure. This creates a gap in the audit trail.
Try adjusting the trunk health check configuration via the API. You need to lower the health_check_interval to something like 5 seconds and set the failure_threshold to 2. This forces the system to switch to the secondary carrier before the SIP 408 fully propagates.
{
"trunk_id": "your_trunk_id",
"health_check": {
"enabled": true,
"interval_seconds": 5,
"failure_threshold": 2,
"recovery_threshold": 3
},
"failover": {
"mode": "active_passive",
"secondary_trunk_ids": ["secondary_trunk_id_1", "secondary_trunk_id_2"]
}
}
Also, ensure your recording export jobs filter by trunk_status changes. If you are exporting for legal hold, you must capture the state change event. A common fix is to add a webhook listener for TRUNK_HEALTH_CHANGED events. This allows you to tag the recordings with the exact timestamp of the health check failure.
[2023-10-27T08:00:01Z] ERROR: SIP 408 Request Timeout - Primary Trunk APAC-1-01 Health Check Failed (Latency: 2500ms)
This log entry is critical. If your bulk export misses this metadata, the chain of custody is broken. You need to map the SIP error code to the trunk health status in your export query. Use the /v2/recordings/search endpoint with a filter for sip_status_code: 408 and trunk_id: your_primary_trunk. This ensures you capture all affected calls for the legal hold request.
You need to adjust the healthCheckInterval in your BYOC trunk configuration to 5 seconds. This forces the load balancer to detect carrier throttling before the SIP 408 timeout occurs.
This is typically caused by the mismatch between traditional SIP health checks and the dynamic routing logic Genesys Cloud expects. In Zendesk, we often relied on simple API status codes, but here the BYOC trunk health is determined by a more complex set of metrics. The default 30-second interval is indeed too slow, as mentioned, but simply changing the healthCheckInterval might not be enough if the failover logic isn’t configured to react immediately to partial failures.
Try adjusting the Trunk Failover Policy in Admin > Telephony > Trunks. Set the Detection Method to ‘SIP OPTIONS’ and lower the Failure Threshold to 2. This ensures the system doesn’t wait for a full timeout before switching. Also, verify that your Carrier Health Check is enabled for each trunk. In my migration from Zendesk, I found that explicit configuration of these thresholds prevents the “active” status false positives during peak hours.