Configure vMix to send a live stream to your Server Room RTMP server. This guide names each field and the value that belongs in it, so it holds regardless of which vMix version you run.
vMix moves its controls between versions, so this guide names the fields and the values that go in them rather than a fixed click path. Look for the labels below wherever your version puts them. Values in UPPERCASE are yours and come from your Server Room account.
You need five values before you open vMix. All of them are in your Server Room account dashboard and in the welcome email sent when your streaming service was set up:
The application name is specific to your service. live is a common value and a common guess, but it is not a default you can assume — using the wrong one is refused by the server. Read yours from your dashboard rather than typing what a general tutorial used.
This is the single most common reason a first vMix stream never connects. In vMix's streaming settings, add a destination and set its type to a Custom RTMP Server. You will then have two distinct fields to fill in.
In the field labelled URL, put the server and the application name — and nothing else:
rtmp://YOUR-SERVER-ADDRESS:1935/YOUR-APPLICATION-NAME
In the separate field labelled Stream Key (some versions label it Stream Name), put only the stream name:
YOUR-STREAM-NAME
Do not paste the whole path into the URL field. This is the shape that fails:
rtmp://YOUR-SERVER-ADDRESS:1935/YOUR-APPLICATION-NAME/YOUR-STREAM-NAMEConcatenated like that, the connection is rejected with a message that does not explain why, which is what makes this one worth checking first.
Fill the Username and Password fields on the same destination with the source credentials from step 1. These authorise you to publish to the server; they are not the same as your Server Room account login.
This matters more than most people expect, and it is worth setting deliberately rather than leaving on whatever the preset chose. In vMix's streaming quality settings, choose a custom quality profile and set:
We cut HLS segments on keyframes. A long or variable keyframe interval produces long, irregular segments, which viewers experience as latency and stalling — and which looks from the outside exactly like a fault on our side. A fixed 2-second interval gives clean, even segments.
Your total output — video bitrate plus audio bitrate together — has to sit comfortably under the upload speed the streaming machine actually gets. As a working rule, keep total output to about a third of your measured upload.
Sensible starting points, then adjust to fit the link you actually have:
Measure the upload from the machine that will be streaming, at the time of day you will be streaming, more than once. The figure your provider advertises and a single speed test are both optimistic. A stream sitting at the edge of its link is the most common cause of "it drops a few times a day" — and from where you are sitting it is indistinguishable from a server problem.
Use a wired connection on the streaming machine. Wireless adds variability that shows up as intermittent drops under exactly this condition.Start the stream in vMix, then confirm it is actually arriving rather than assuming it is. Open your playback URL in a player:
http://YOUR-SERVER-ADDRESS:1935/YOUR-APPLICATION-NAME/YOUR-STREAM-NAME/playlist.m3u8
Give it a few seconds — the first HLS segments have to be written before anything will play.
vMix reconnects automatically, and it has no on/off control for it. If you have been told to enable auto-reconnect in vMix, there is no such checkbox to find — the behaviour is already on. Nothing needs configuring here.
Be clear about what that does and does not buy you: automatic reconnection changes how gracefully a stream recovers, not whether the interruption happens. If your upstream link drops, viewers see the drop. If drops are recurring, the setting worth revisiting is the bitrate in step 5.
Common questions about configuring vMix for live streaming with Server Room.
