Multistreaming Without the Meltdown: Restream Services vs. Self-Hosted RTMP
One stream, four platforms. We compare relay services against running your own RTMP restream — cost, latency, and what breaks at scale.
Streaming to one platform is plumbing. Streaming to four is an architecture decision. The two real options — a hosted relay service or your own RTMP restream server — differ on cost, latency, and who’s awake when it breaks.
Option A: Hosted Relay (Restream, Castr, and friends)
You send one stream upstream; the service fans it out to your platforms.
What you get: zero infrastructure, per-platform chat aggregation, transcoding to each platform’s preferred specs, analytics.
What it costs: subscription fees, an added latency hop (typically +2–8 seconds), and a dependency — when the relay hiccups, all your platforms fail together.
The bandwidth math is the quiet win: you still only upload one 6 Mbps stream. Your home connection never multiplies.
Option B: Self-Hosted RTMP Restream
Run nginx-rtmp or a MediaMTX instance on a cheap VPS. Your encoder pushes to your server; it relays to each platform.
A minimal nginx-rtmp fan-out looks like:
rtmp {
server {
listen 1935;
application live {
live on;
push rtmp://ingest-a.example/app/KEY_A;
push rtmp://ingest-b.example/app/KEY_B;
}
}
}
What you get: control (arbitrary destinations, custom transcodes with ffmpeg), no per-platform subscription, and a fixed cost (~$5–10 VPS).
What it costs: you’re the on-call engineer now. There’s no dashboard warning when a push target’s ingest changes; you find out from viewers.
The Comparison That Actually Matters
| Factor | Hosted relay | Self-hosted |
|---|---|---|
| Setup time | ~20 min | Half a day first time |
| Added latency | +2–8s | +1–3s (pick a near VPS) |
| Per-platform transcode | Automatic | DIY with ffmpeg |
| Failure mode | Support ticket | Your pager |
| Chat aggregation | Built-in | Separate tooling |
When Each Wins
Hosted relay when: you stream irregularly, you value chat aggregation, or nobody on the crew wants to own a server. The subscription is cheaper than the maintenance hours.
Self-hosted when: you stream constantly (subscription math inverts), you need unusual destinations, or you want transcoding control — like pushing a 1080p feed to one platform and a 720p to another, which relay services often gate behind tiers.
The Hybrid That Works
Run the relay for chat and analytics, but keep a hot spare direct RTMP output configured in OBS. When the relay degrades, one click fails over to direct-platform streaming. We’ve used this exactly twice in a year — both times it saved the show.
The Bottom Line
Multistreaming’s real cost isn’t bandwidth — it’s operational complexity. Buy the relay if you’d rather spend that complexity on the show itself.