Stayin' Alive, Stayin' Alive

There are two questions every station Mac has to answer, and most stations only think about the first one.

The first: how do I keep this Mac from restarting when I don't want it to? The second, which matters just as much: when it restarts anyway, will it come all the way back on its own?

Because it will restart, eventually. A power flicker, an update, a crash, a well-meaning person pressing the wrong button. At 3 a.m. on a Sunday, nobody is standing there to help it. The stations that stay on the air through all of that aren't lucky. They've made sure every link in the chain between “power comes back” and “music is playing” works without a human.

We covered the sleep and power-failure settings in Keeping Your Mac Awake for 24/7 Broadcast. This article is about the rest of the chain, including a new wrinkle in recent versions of macOS that can quietly break it.

Fewer Surprise Restarts

Start by reducing how often it happens.

• Automatic updates. The classic culprit. macOS can download an update, install it overnight, and restart, all on its own. Turn off automatic installation under System Settings → General → Software Update → Automatic Updates, and update on your own schedule instead, at a time when you can watch the Mac come back up. That goes double for major releases. macOS 27 (“Golden Gate”) arrived on September 14, and it's the kind of update to try when someone can be there, not the night before a big broadcast.
• A battery backup. A small UPS (uninterruptible power supply) rides through the short power blips that cause many surprise restarts, and gives the Mac a chance to shut down cleanly during a longer outage. For a machine that runs a radio station, it's inexpensive insurance.

Now Make the Comeback Automatic

You can't prevent every restart, so plan for one. Picture what has to happen, in order, for the station to get back on the air with no one there:

1. Power returns, and the Mac starts by itself. That's the Start up automatically after a power failure setting.
2. The Mac reaches the desktop by itself. No password prompt in the way.
3. AutoCast launches by itself.
4. AutoCast resumes where it left off.
5. You find out it happened.

Every one of those has to work. The chain is only as strong as its weakest link, and step 2 is where a lot of stations are about to get a nasty surprise.

The FileVault Wrinkle

FileVault is Apple's disk encryption. It's a good security feature, and for a laptop that travels, it's the right default. But it works by requiring a password at startup, before the Mac will even unlock its disk. After every restart, the Mac stops at a login screen and waits for a human to type it. Automatic login isn't available while FileVault is on.

For a station Mac, that's the whole ballgame. Power blips at 3 a.m., the Mac restarts, and it sits at the password screen while your station is silent, until somebody drives over.

Here's what's new: Apple has been steadily pushing FileVault onto more Macs. Beginning with macOS 26 Tahoe in 2025, setting up a Mac with an Apple Account turns FileVault on automatically. (Set up with a local account and the installer offers it, but you can skip it.) macOS 27 continues to prompt for it during setup. So a station Mac that was set up recently, or upgraded, may have FileVault turned on without anyone having chosen it. It's worth checking every Mac you set up or update.

There's a trade-off, and it's worth being honest about it. With FileVault off, the disk isn't encrypted, so anyone who gets physical possession of the Mac could read what's on it. For a Mac in a locked studio holding a music library and a program log, most stations will judge that a fair price for a station that recovers on its own. If you can't accept it, Apple does offer a partial workaround: on Apple silicon Macs running macOS 26 or later, FileVault can be unlocked over SSH after a restart if Remote Login is turned on and the Mac has a network connection. But somebody still has to do the unlocking after each restart, so it isn't unattended recovery.

The AutoCast Side of the Chain

Once the Mac is back at a desktop, AutoCast has a few pieces of its own that finish the job.

Then Test It

Here's the part almost everyone skips: actually restart the Mac and watch what happens. Do it during a quiet hour, with time to spare, and see whether it gets all the way back without you touching anything. Does it reach the desktop with no password prompt? Does AutoCast launch? Does it resume at the right place in the log? Did the alert email arrive? If any step needs you, you've found your weak link, and you found it on your schedule instead of at 3 a.m.

Repeat the test after any major macOS update, because that's exactly when settings like FileVault can change without anyone deciding to change them.

Quick Checklist

1. Automatic macOS installs: off. Update deliberately, when you can watch.
2. A UPS on the station Mac.
3. Start up automatically after a power failure: on (see Keeping Your Mac Awake).
4. FileVault: off, and automatic login: on, with the physical security to match.
5. AutoCast set to launch at login.
6. Reboot Recovery on in AutoCast's System settings.
7. Alert emails on, and tested.
8. Restart the Mac on purpose and watch it come all the way back. Repeat after major updates.

None of this is exciting, and that's the point. The best day for a station Mac is the one where a power blip happens at 3 a.m. and nobody ever finds out.

Sources: Apple Platform Deployment (FileVault unlock over SSH on Apple silicon, macOS 26 or later); TidBITS, “macOS 26 Tahoe Pushes FileVault Use” (September 2025); AutoCast Help, “Keeping AutoCast Running.”