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Make a Mac mini restart after a power failure

How to get a Mac mini to power back on by itself after a power cut on macOS Tahoe (macOS 26) — the new 26.5 Energy setting, pmset autorestart, auto-login so services return, and the FileVault catch-22 that blocks unattended restart.

Problem summary

I'm here because I run a Mac mini as a server and want it to turn itself back on and resume after a power cut — without me pressing the power button or typing a password. macOS Tahoe added a proper Energy setting for this, and `pmset` has long had a flag too. But powering on is only half of it: the mini also has to log in and restart its services, and FileVault blocks that unattended login. This page sets up true hands-off recovery and is honest about the encryption trade-off you have to make.

Operator snapshotEvidence first
First proof

Enable Energy → 'Start up automatically after a power failure' (Tahoe 26.5).

Screen to open

sudo pmset -a autorestart 1

Expected signal

The mini powers on when mains power returns.

Stop boundary

Don't disable FileVault on sensitive/travelling Macs without weighing it.

Layer path

1Hands-off recovery from a power cut is a chain, not a single setting: power returns → the Mac powers on → it logs in → its services restart → it's reachable. The auto-power-on setting only covers the first link; people stop there and wonder why the server is up but not serving.
2The link that breaks unattended recovery is login. After a power cut, services that need a session don't start until someone logs in — so automatic login is mandatory. And FileVault sits directly across that link: it requires the disk to be unlocked with credentials at boot, which no one is there to enter, so the chain stalls at the unlock screen.
3That makes this fundamentally a security trade-off, stated honestly: full-disk encryption vs unattended restart. The mitigation is to encrypt the data volume separately and leave the boot disk unencrypted — encryption where it matters, hands-off boot where you need it — plus a UPS so the power event is clean in the first place.
Runbook

Step-by-step runbook

Start here. Do each check in order, compare it to the expected result, and stop when the evidence explains the failure or the safe stop point applies.

1

Enable power-on

Check: Energy 'start up automatically after a power failure' (26.5) or `pmset -a autorestart 1`.

Expected result: The mini powers on when mains returns.

If not: Use pmset if the Energy option is absent.

2

Enable auto-login

Check: Set Automatic login in Users & Groups.

Expected result: The mini reaches a session so services start.

If not: If greyed out, resolve FileVault next.

3

Resolve FileVault

Check: Disable FileVault for hands-off restart, or encrypt the data volume separately.

Expected result: The power-on → login chain completes unattended.

If not: Keep FileVault + manual unlock only if the data demands it.

4

Make services restart

Check: Run services as launchd jobs with RunAtLoad + KeepAlive.

Expected result: Every service returns after the unattended boot.

If not: Add ordering for network-dependent services.

5

Add a UPS and test

Check: Pair a UPS, then cut and restore power and watch the full chain.

Expected result: Power-on → login → services reachable, hands off.

If not: Isolate and fix whichever link stalls.

Decision tree

Decision tree

If: Mini stays off after power returns.

Then: Auto power-on isn't enabled.

Action: Enable the Energy toggle (26.5) or `sudo pmset -a autorestart 1`.

If: Mini powers on but sits at a password/unlock screen.

Then: FileVault is on, blocking unattended login.

Action: Disable FileVault for hands-off restart, or accept manual unlock.

Safe stop: Don't disable FileVault on sensitive/travelling Macs without weighing it.

If: Mini logs in but services don't start.

Then: Services are login items or LaunchAgents without a session.

Action: Enable auto-login and run services as launchd jobs (KeepAlive).

If: Services start but fail on missing network/mount.

Then: They launched before the network or a share was ready.

Action: Add launchd ordering or a short startup delay for network-dependent services.

If: Data is sensitive but you need unattended restart.

Then: FileVault-on conflicts with hands-off boot.

Action: Leave the boot disk unencrypted; put sensitive data on a separately-encrypted external/NAS volume.

Evidence

Evidence table

SymptomEvidence to collectLikely layerNext action
Mini doesn't come back after an outage.Energy toggle off; `pmset` autorestart 0.Auto power-on not set.Enable the toggle / `pmset -a autorestart 1`.
Powers on, waits at unlock screen.FileVault is enabled.FileVault blocking unattended login.Disable FileVault, or encrypt data volume separately.
Boots and logs in, but Plex/SMB down.Services are 'Open at Login' items.No launchd jobs.Convert to LaunchDaemon/LaunchAgent with KeepAlive.
Services crash on boot citing no network/mount.They launched before the network/share was ready.Startup ordering.Add launchd dependencies or a delay.
Filesystem oddities after repeated outages.No UPS; hard power cuts.Abrupt power loss.Add a UPS; run First Aid after a hard cut.
Reference

Commands and settings paths

Enable automatic restart after power loss

sudo pmset -a autorestart 1

Where: Terminal on the Mac.

Expected: `pmset -g | grep autorestart` then shows 1 — it restarts when power returns.

Failure means: If unsupported on the model, the key won't stick.

Safe next step: Use the Energy 'start up automatically after a power failure' toggle instead.

Verify the power-management settings

pmset -g

Where: Terminal on the Mac.

Expected: Shows autorestart, sleep, and related values in one view.

Failure means: autorestart 0 or sleep non-zero means the server won't recover/stay up.

Safe next step: Set autorestart 1 and sleep 0 for an always-on server.

Schedule a recurring power-on (optional)

sudo pmset repeat poweron MTWRFSU 09:00:00

Where: Terminal on the Mac.

Expected: `pmset -g sched` shows the schedule; the mini powers on daily at the set time.

Failure means: This is separate from after-outage autorestart.

Safe next step: Use only if you deliberately want scheduled wake, not just outage recovery.

Confirm automatic login is configured

System Settings → Users & Groups → Automatically log in as

Where: Settings on the Mac.

Expected: Set to the server account so boot reaches a session.

Failure means: Greyed out means FileVault is on and blocking it.

Safe next step: Resolve FileVault (disable, or separate-volume encryption).

Hardware boundary

Hardware and platform boundary

Change only when

  • Add a UPS sized to ride out brief outages and trigger a clean shutdown on long ones — it pairs with auto-restart for true resilience.
  • If the server needs both encryption and unattended restart, plan storage so sensitive data lives on a separately-encrypted volume, not the boot disk.

Evidence that matters

  • A model/point release that exposes auto power-on (Energy toggle or `pmset autorestart`).
  • A UPS for clean power handling, not just the restart setting.
  • A storage layout that lets you leave the boot disk unencrypted while protecting real data.

Evidence that does not matter

  • Wake-on-LAN reliability — irrelevant when the goal is power-on-after-outage.
  • Raw performance specs — recovery is about power/login/launchd, not speed.
  • The exact idle wattage — relevant to power cost, not to restart behaviour.

Avoid

  • Disabling FileVault on a sensitive/portable Mac purely for unattended restart.
  • Relying on auto power-on without auto-login + launchd (it boots but won't serve).
  • Running an unprotected server through frequent hard outages without a UPS.

Related tool/checklist

Use the linked tool when you need a guided plan from your exact symptoms instead of a static checklist.

NAS setup planner

Related problems

UPS beeping after outage

Last reviewed

2026-06-02 · Reviewed by HomeTechOps. Reviewed against Apple's macOS 26 update notes, automatic-login, and FileVault documentation; models unattended recovery as a power-on → login → services → reachable chain, centres the FileVault/auto-login catch-22 as the crux, and is explicit that disabling FileVault is a deliberate security trade-off (mitigated by separate data-volume encryption) paired with a UPS.

Sources/assumptions

  • Assumes a Mac mini (or other desktop Mac) on macOS Tahoe (macOS 26) used as an always-on server; the 26.5 'start up automatically after a power failure' option should be re-verified against your exact point release.
  • `pmset autorestart` follows Apple's documented power-management behaviour; not every Mac exposes every pmset key.
  • The FileVault interaction (auto-login unavailable while FileVault is on) is Apple's documented behaviour and is the crux of unattended restart.

Source-backed checks

HomeTechOps turns official docs and conservative safety rules into a shorter runbook. These links are the source trail for the page direction.

Apple Support: macOS Tahoe 26 — what's included in the updates (KB 122868)Authoritative per-point-release version + date list for macOS Tahoe 26.x; cited to pin which point release a Time Machine / Wi-Fi / dock symptom maps to.Apple Support: How to log in automatically to a Mac user accountUsed for enabling automatic login so a headless server's services start without manual sign-in, and the rule that automatic login is unavailable while FileVault is on.Apple Support: Set a FileVault recovery key on MacUsed for the rule that the FileVault recovery key must be kept somewhere other than the encrypted startup disk, and that a Time Machine backup encrypted with a lost key is unrecoverable.