Does anyone know why our SIP trunks are throwing 408 Request Timeout errors specifically when the WFM schedule publish job runs in the Chicago environment?
We are running Genesys Cloud version 2023.11. We publish schedules every Tuesday at 6:00 AM CST. This is a critical time because it coincides with the start of our high-volume inbound shifts. The issue started appearing after we increased our concurrent call volume by 15%.
The problem manifests as follows: when the schedule publish API call completes, there is a brief spike in CPU usage on the server handling the SIP signaling. During this spike, about 5-10% of incoming calls on our primary SIP trunk fail with a 408 Request Timeout. The calls are not dropped immediately; they ring for about 10 seconds before failing. This is extremely frustrating because it happens right when agents are logging in and ready to take calls.
We have checked the SIP trunk health dashboard, and the status remains “Active” throughout the publish window. However, the latency metrics show a significant increase during the exact minutes the schedule is being published. We suspect there is a resource contention issue between the WFM service and the telephony signaling service.
Has anyone encountered a similar issue with schedule publishing affecting SIP trunk performance? We are considering splitting the schedule publish into smaller batches to reduce the CPU spike. Alternatively, we might need to adjust our SIP trunk timeout settings, but we are hesitant to do that without understanding the root cause.
Any insights or workarounds would be greatly appreciated. We are under pressure to resolve this before next week’s publish.
If you check the docs, they mention that WFM schedule publication is a heavy database operation that can cause transient latency spikes in the tenant’s underlying infrastructure, which directly impacts the responsiveness of the SIP trunk registration keep-alives during that specific window. When the schedule publish job runs, it locks certain resources, causing the initial SIP INVITE requests to experience delays that exceed the default 20-second timeout threshold configured on many enterprise Session Border Controllers (SBCs). This is not necessarily a Genesys Cloud defect but rather a timing collision between high-availability infrastructure maintenance and real-time media signaling. The solution involves adjusting the SIP trunk timeout settings within the Genesys Cloud architecture configuration to allow for a slightly longer grace period during known peak maintenance windows. You should navigate to Administration > Telephony > Trunks and locate the specific BYOC or Genesys-hosted trunk experiencing the 408 errors. In the advanced configuration section, increase the “Initial Offer Timeout” from the default 20 seconds to 30 or 40 seconds. This provides additional buffer time for the SIP handshake to complete despite the temporary latency introduced by the WFM process. Additionally, review the “Retry Logic” settings to ensure that failed INVITEs are retried immediately rather than being dropped after the first timeout. While this does not eliminate the root cause of the latency, it prevents the 408 Request Timeout from terminating the call setup prematurely. It is also advisable to coordinate with your network team to monitor the SBC logs during the Tuesday 6:00 AM CST window to confirm that the increased timeout resolves the issue without introducing other side effects such as delayed ringing.