Resolving Cloud Transcoder Streaming Failures: Rectifying Multi CDN Output Structures in RAW Transcoding Modes

Issue Description

The cloud transcoder task initializes successfully, but the live broadcast terminates without generating the expected Amazon Interactive Video Service recording assets. Although the active session is configured to simulcast the media stream concurrently to both Amazon Interactive Video Service and YouTube, only the YouTube egress route functions partially before the global cloud task stops unexpectedly.

Platform/SDK

• Implementation: iOS Mobile

• Cloud Infrastructure: Cloud Transcoder

Error Characterization

The Notification Center Service intercepts critical event logs and failure signaling states before the session teardown:

• NCS eventType 121: RTMP push failure on the YouTube output with error code 32

• NCS eventType 111: Task stop with reason RtcPullerError

Root Cause

The multi platform delivery failure originates from an invalid payload structure inside the cloud transcoder start request schema.

When the configuration parameters designate the video option mode as RAW for concurrent multi CDN content distribution, the injection parser requires an atomic configuration envelope. All target destination streaming uniform resource locators must be consolidated within a single outputs structural block, nested inside a continuous streamUrl array primitive.

In this failure mode, the application request passes two distinct, separate outputs objects, allocating one block for Amazon Interactive Video Service and a separate parallel block for YouTube. This multi object structure violates the schema validation rules enforced for the RAW encoding pipeline path.

As a result of this malformed payload, the cloud ingestion parser accepts the job but induces volatile internal routing states. The YouTube deployment routine executes but terminates later with a standard streaming push error code 32. Concurrently, the Amazon Interactive Video Service module never initializes its network publish session, preventing asset creation. The infrastructure detects this output continuity breakage and forcefully terminates the parent task under a puller error state.

Solution and Resolution Steps

1. Consolidate Target Uniform Resource Locators 

   Correct the start request configuration format for simultaneous multi CDN deployment under RAW mode. Consolidate the destination addresses into a single unified outputs object array, mapping all edge stream addresses within one sequential array as demonstrated in the following layout:

{
  "outputs": [
    {
      "streamUrl": [
        "rtmps://example-ivs-url",
        "rtmp://example-youtube-url"
      ],
      "audioOption": {
        "profileType": "AUDIO_PROFILE_MUSIC_STANDARD"
      },
      "videoOption": {
        "mode": "RAW"
      }
    }
  ]
}

2. Instantiate Segregated Transcoder Tasks 

   If different target live platforms demand completely unique profile attributes or independent audio and video parameter sets, abandon the single simulcast request. Instead, programmatically launch two entirely separate cloud transcoder task instances to maintain pipeline isolation.

3. Align with Stricter System Validation Benchmarks 

   Recognize the architectural constraints enforced across deployment environments. Historical cloud builds permitted structural schema anomalies but produced unpredicted runtime failures. Server framework updates rolled out after late April 2026 apply rigid structural validation on the gateway layer, forcefully returning a standard HTTP 400 Bad Request status code for multi object syntax to prevent malformed tasks from initiating.