"Backend Failed to Respond to a Heartbeat" — BeamMP Keymaster Is Down, Your Server Isn't

If your BeamMP server console is filling up with this every thirty seconds, you are not broken:

[WARN] Backend failed to respond to a heartbeat. Your server may temporarily
disappear from the server list. This is not an error, and will likely resolve
itself soon. Direct connect will still work.

Read the last sentence of BeamMP's own warning, because it is the important one: direct connect will still work. Your server is running. Your mods are fine. Your auth key is fine. What has stopped working is BeamMP's own backend — the service every server on the planet checks in with so it can be listed in the in-game browser.

As of 29 August 2026 that backend, and the Keymaster site that issues auth keys, are down for maintenance. Here is what is actually happening, what you can safely ignore, and the one setting that gets your friends back onto your server today.

BeamMP has said it themselves

Load keymaster.beammp.com right now and you don't get the key dashboard. You get a maintenance page titled "Keymaster Temporarily Offline":

The old Keymaster is unavailable while we carry out maintenance. It isn't possible to sign in or manage keys here right now. Nothing needs to be done on your side — please check back a little later. You can still run your server in the meantime — it just has to be in private mode, so it won't be shown on the server list. Please don't contact the support team about this — they can't help with it.

That is BeamMP's wording, not ours. Two things follow from it. First, this is planned maintenance on their side and there is nothing for you to fix. Second — and this is the part most people miss — the workaround is private mode, which we'll come to below.

The word "old" in "the old Keymaster" is worth noting too. It reads like a migration to their newer account system rather than a crash, which usually means it comes back on a schedule rather than at 3am after someone reboots a box.

What's up, what's down

We run 3,116 active BeamMP servers, so we can measure this rather than guess at it. Checked at 04:56 UTC on 29 August:

That last row is the whole reason your server still works. Listing and joining are two different services. The one that puts you in the browser is down; the one that lets a player through your door is not.

It isn't your host, and here's the proof

The instinct when a server misbehaves is to blame whoever you rent it from. Fair enough — so here's the test that settles it, and you can run a version of it yourself.

A single host's network problem shows up on that host's machines. An upstream outage shows up everywhere at once, to the second. When we swept our fleet this morning, servers on 20 of our 24 machines were logging the heartbeat warning, and the failure runs were identical: a continuous 285-minute streak on a machine in the United States, another 285-minute streak in Germany, another in Finland — all beginning within a couple of minutes of each other and all still running as we write this.

Independent machines in three countries cannot fail at the same second for a local reason. And the public server list agreeing with them — 2 servers, nobody online, on a game that normally fields hundreds — is the same story from the other direction.

If you host elsewhere, the equivalent check is simply to open the in-game server browser. If it's empty or nearly empty, nobody's server is listed, and yours being missing is not personal.

Your server is still running — and people can still join

This is the bit worth shouting about. During this outage we have watched real players connect and play on servers across our fleet:

• A private server that booted during the outage reached ALL SYSTEMS STARTED SUCCESSFULLY, logged zero heartbeat warnings, and took a player join a few hours later.
• Another one started at 03:00 UTC this morning, deep inside the outage window, and had players identified and in by 03:19.
• Even a public server that had racked up 709 heartbeat warnings still logged a successful player join at 00:53 UTC.

Nobody's save is gone. Nobody's mods are broken. The only thing you've lost is the shop window.

How your players get in

Send them your IP and port — the same connection details on your server's dashboard page. In BeamMP they go to the Direct Connect tab in the multiplayer menu, put the IP in the top field and the port in the bottom field, and connect. That path doesn't touch the server list at all. If your players have never used it, our guide to playing BeamMP walks through the multiplayer menu.

The one setting to change: Private = true

Here's the mechanism behind BeamMP's "it just has to be in private mode" line, and why it matters more than it sounds.

A public server must register with BeamMP's backend before it will accept anybody. With Private = false, the server boots, tries to check in, can't, and holds the door shut — every player who tries gets:

[INFO] Client kicked: The server is still starting, please try joining again later.

A private server skips registration entirely. With Private = true it reaches ALL SYSTEMS STARTED SUCCESSFULLY in about six seconds and takes direct-connect joins immediately. We proved this side by side on two identical servers on the same machine back in August: the public one never finished starting and failed a heartbeat every 30 seconds forever; the private one was up in six.

So:

• Server already running and taking joins? Leave it completely alone. It registered before the outage and it will keep working. Do not restart it — a restart is what drops you into the "still starting" trap.
• Server restarted during the outage and now kicks everyone with "the server is still starting"? Set Private = true, restart once, and hand out your IP and port. On Connect Hosting that's Dashboard → your server → Server Settings. Elsewhere it's the Private line in ServerConfig.toml.
• Flip it back to false once BeamMP is healthy and you want to be listed again.

The trade-off is exactly the one BeamMP describes: private means you're not in the public browser. During an outage where the public browser is empty anyway, you are giving up nothing.

But the AuthKey field still has to have something in it

This trips people up constantly, and it matters more than usual right now: AuthKey must not be blank, or the server will not start at all — private mode or not.

BeamMP ships the reason in its own config file: "AuthKey has to be filled out in order to run the server." Leave the line as AuthKey = "" and the binary refuses to boot. We caught exactly that in August on a freshly built server whose install script wrote an empty key — it wouldn't start until we put a value in, and then it reached ALL SYSTEMS STARTED SUCCESSFULLY in about five seconds.

The part that surprises people is that the value doesn't have to be valid. It doesn't have to be a real key, or a UUID, or the right length. It just has to not be empty. A placeholder boots. A key you generated a year ago and deleted boots. A dead key boots.

Validity decides one thing only: whether your server gets listed publicly. It has nothing to do with whether it runs.

So if you're setting up a server today and can't generate a key because Keymaster is offline, you're not blocked. Put a placeholder in the field — something UUID-shaped like 00000000-0000-0000-0000-000000000000 is fine — set Private = true, and play on direct connect. Swap in your real key whenever Keymaster comes back.

If you're hosting with us this is already handled: we seed a placeholder key at provisioning, so a new server boots and runs without you having to find a key first.

What you must not do is empty the field. If you're tempted to "clear it out and start fresh" while the key can't be checked, don't — a blank field is the one state that turns a cosmetic warning into a server that genuinely won't start.

What not to do

Most of the damage done during an outage like this is self-inflicted, by people trying to fix a thing that isn't theirs to fix.

• Don't regenerate your auth key. You can't anyway — Keymaster is down — and your existing key is not the problem.
• Don't clear or empty the AUTHKEY field. A blank key is the one value that genuinely stops BeamMP from booting — the field needs some text in it, valid or not. Leave it exactly as it is.
• Don't reinstall the server. On most hosts a reinstall resets your config, and on some it takes your mods with it. You'd be trading a cosmetic warning for a real outage.
• Don't sit there restarting. Each restart of a public server during the outage risks leaving it stuck at "still starting."
• Don't open a ticket with BeamMP. Their own maintenance page asks you not to: "they can't help with it."

Three log lines that look alike and mean different things

Worth learning the difference, because they get confused constantly and only one of them is BeamMP's problem to fix.

Notably, across our fleet during this outage we've seen zero servers logging Backend REFUSED the auth key. Nobody's key has died. The keys are simply un-checkable while the service that checks them is offline.

And one more, since it comes up every single time: if your server genuinely won't start, or players get in and things are broken, the cause is almost always a corrupted or stale mod rather than anything to do with heartbeats — a bad zip in Resources/Client, or mods that went stale after a BeamNG game update. The heartbeat warning is noise; the log line tells you so itself.

When Keymaster comes back

Nothing is required of you.

• Your server heartbeats every 30 seconds, so it re-registers and reappears in the browser on its own, usually within a minute. No restart needed.
• If you switched to Private = true, switch it back to false to be listed again.
• If you never had an auth key, this is when you get one: sign in at Keymaster, create a key, and paste it into your server's AUTHKEY setting. Until then your server runs perfectly well in private mode on direct connect — a key is what gets you listed, not what gets you running.

Frequently asked questions

Is "Backend failed to respond to a heartbeat" an error?

No, and BeamMP's own message says so: "This is not an error, and will likely resolve itself soon." It's a warning that your server couldn't check in with the public list. The server keeps running and keeps accepting direct connections.

Can people still play on my server while BeamMP's backend is down?

Yes. Give them your IP and port and have them use the Direct Connect tab. We've confirmed real players joining servers across our fleet throughout this outage. If your server is public and kicking people with "the server is still starting," set Private = true and restart once.

Why is the BeamMP server list empty?

Because servers register on that list by heartbeating to BeamMP's backend, and that backend is down. With no check-ins arriving, entries expire and the browser empties out. It refills by itself once the backend returns.

Do I need a new auth key?

No. Your key is fine — and you couldn't generate one right now if you wanted to, because Keymaster is offline. An auth key controls whether your server is listed publicly; it isn't what makes your server run.

I don't have an auth key and Keymaster is down. Can I still run a server?

Yes. The AuthKey field just has to contain something — it doesn't have to be a valid key. Put a placeholder in it, set Private = true, and play via direct connect. An empty field is the only value that stops the server booting. Generate the real key once Keymaster is back.

How long will this last?

BeamMP hasn't given a time, only "please check back a little later," with updates going to their Discord. The "old Keymaster" wording suggests scheduled migration work rather than an unplanned failure, so it's likely to end on their schedule rather than drag on.

My server won't start at all. Is that this?

Probably not. A backend outage doesn't stop a server booting — private servers have been starting fine right through it. If yours won't start, look at your mods first: a corrupted or truncated zip in Resources/Client, or mods left stale by a BeamNG update. Check that the AUTHKEY field isn't empty, too — the field needs some text in it, valid or not, and blank is the one value BeamMP refuses to boot on.

The short version

BeamMP's Keymaster and backend are down for maintenance. Your server is running, your key is fine, and your mods are fine. Don't empty the AuthKey field — it needs some text in it, valid or not, or the server won't start. Hand your players your IP and port and they can play today. If your server is public and stuck at "still starting," flip it to private, restart once, and carry on. Everything goes back to normal on its own when BeamMP's side comes back — no reinstall, no new key, nothing to fix.

We'll update this post when Keymaster is back. If you're hosting with us and your server is stuck, open a ticket and we'll set it to private mode and check your logs for you.