Publishing RTMP¶

media.publish.rtmp

The source connects to Sapsan and sends the stream. This is publishing; client capture from a remote server belongs to media.ingest.

Configuration¶

In the console, open the stream, add an explicit Publish input at the desired position, and set its key in the input card. Enter a key manually or click Regenerate key: at least 5 Latin letters, digits or ._-. The setting is inputs[index].publish.rtmp_streamkey; setting a key does not add or reorder inputs. There is no upper length limit. Regeneration creates a random 10-character key.

The field hides the key. Use the copy button to configure the encoder; the eye temporarily reveals the value.

listeners:
  rtmp:
  - port: 1935
streams:
- name: studio
  inputs:
  - publish:
      rtmp_streamkey: Abc012._-Z

In OBS, set the server to rtmp://server:1935 and the key to Abc012._-Z. With the central API, use PATCH /central/api-v4/streams/configs/studio with body {"inputs":[{"publish":{"rtmp_streamkey":"Abc012._-Z"}}]}. The inputs array is replaced as a whole: include all other inputs in order, with every setting and secret.

When a working source precedes publish, the RTMP or SRT encoder is accepted as standby. Once the primary recovers through the clean window, the encoder stays connected as standby. A second encoder is rejected, even while the first is standby or has not sent usable frames. Switching to video publishing waits for the next keyframe; audio-only waits for a usable audio frame. Existing source and transport timeouts apply.

Authentication¶

The key authorizes RTMP publishing to the single explicit publish input. Without a key, including publish: {}, RTMP is denied; the stream name does not replace the secret. Central atomically validates uniqueness across the current cluster configuration, including disabled streams. Used-key history is not stored. Validation rejects a second publish input and publish inside MBR.

After applying a changed or cleared key, the server disconnects the current RTMP publisher and rejects the previous key. Clearing rtmp_streamkey: null keeps the publish input. Changing the RTMP key preserves SRT publishing; other configuration changes preserve the RTMP connection when its key is unchanged.

Transport¶

RTMP over TCP. The sender connects to the shared server RTMP listener.

Supported codecs¶

H.264
HEVC (Enhanced RTMP, hvc1)
AV1 (Enhanced RTMP, av01)
AAC
MP3

RTMP carries FLV messages; Enhanced RTMP identifies video codecs by FourCC. The list describes receiving compressed frames and passing them into the pipeline. AV1 requires Enhanced RTMP with av01; selecting AV1 at the sender without this packaging is insufficient. MP3 is accepted as FLV audio, separately from AAC.

Error handling¶

A stream accepts one active publication at a time. When the connection ends, the source becomes unavailable and shared failover rules apply. The sender initiates reconnection.