What is Custom RTMP?
Custom RTMP is a user-configured Real-Time Messaging Protocol destination for publishing a live audio-video feed. Its endpoint normally consists of a server URL and a destination-specific stream key.
How Custom RTMP works
Custom RTMP configuration exposes a generic publish target instead of a platform-specific account connection. An encoder opens a persistent session to the supplied RTMP server, publishes under an application path and stream name or key, and sends encoded audio-video messages as the event runs. The receiving service may then transcode, record, or repackage the feed for viewers. It is an ingest boundary, so endpoint secrecy, reconnect behavior, codec expectations, and monitoring determine operational reliability.
Key facts
- RTMP commonly carries H.264 video and AAC audio in live publishing workflows, but the receiving server’s accepted codec and parameter set—not the protocol name alone—controls compatibility.
- Stream keys function as routing credentials on many endpoints and should be kept out of client code, logs, and screenshots; rotation is appropriate after disclosure.
- A TCP connection can succeed while publishing still fails because the application path, stream name, authorization, or media parameters are rejected later in the RTMP session.
When Custom RTMP matters
Configure custom RTMP when broadcasting to a private server or a destination without a built-in integration. A wrong URL, expired key, unsupported codec, or blocked port can prevent the stream from connecting.