Thoughtful, detailed coverage of the Mac, iPhone, and iPad, plus the TidBITS Content Network for Apple consultants.

Use Time Machine with the 802.11ac AirPort Extreme Base Station

In betas of Mac OS X 10.5 Leopard, Apple introduced a feature that enabled Time Machine backup to a USB hard drive attached to an AirPort Extreme Base Station. However, by the time Leopard shipped, Apple had pulled the feature (see “Time Machine via AirPort Disk Is Unsupported, Apple Says,” 7 April 2008), focusing networked Time Machine backups on the Time Capsule (now called AirPort Time Capsule). On subsequent updates to Mac OS X, we checked to see if the feature had returned, and some users managed to make it work, but Apple steadfastly maintained that backing up to an AirPort Disk was unsupported, and eventually we stopped looking.

In fact, Apple still makes that statement in “AirPort base stations: Time Machine hard drive compatibility,” saying clearly:

“Time Machine is not supported with USB hard drives that are connected to an AirPort Express or AirPort Extreme device.”

But a release note for the recent “AirPort Base Station Firmware Update 7.7.2” (21 November 2013) caught my eye while I was editing our coverage (this update applies only to the newest 802.11ac base stations released in June 2013). Apple says:

“Addresses an issue that prevents a USB hard drive connected to an AirPort Extreme from appearing as an available disk in Time Machine”

And once I went looking for confirmation, I found it in Apple’s “Mac Basics: Time Machine backs up your Mac” document, which says:

“Time Machine can only back up to an external drive connected to an AirPort Extreme 802.11ac base station. Time Machine cannot back up data to external drives connected to other AirPort Extreme base station models”

That’s in complete contradiction to the 5-year-old prohibition against pointing Time Machine at an AirPort Disk, and the change has gone almost entirely unnoticed since June 2013, despite being prominently mentioned on page 13 of the manual for the new AirPort Extreme Base Station. Apparently, Mac users really don’t usually read the manual.

In fact, someone did notice — the late Time Machine expert James “Pondini” Pond called it out on his site in June; alas, he passed away in September 2013 at the age of 70 and will be missed.

What’s most compelling about backing up to an AirPort Disk, as opposed to an AirPort Time Capsule, is that you’re not combining two entirely unrelated pieces of hardware in one package. If the AirPort Time Capsule’s hard drive fails, it’s difficult to replace, and if you want to upgrade the wireless gateway side of the equation, there’s no easy way to bring your backups over to the new device. With an AirPort Extreme Base Station and attached USB hard drive, you gain more flexibility.

I don’t have one of the new 802.11ac AirPort Extreme Base Stations to test the return of Time Machine backups to AirPort Disks, and everything I’ve read indicates that it works only with the newest hardware, not any of the older, flatter base stations. Nevertheless, if you have the necessary hardware and curiosity, I’d encourage you to hook up a USB hard drive and see if Time Machine backs up to it reliably (since 10.8 Mountain Lion, Time Machine has allowed you to back up to multiple destinations, alternating between the different destinations). Let me know how it works out in the comments!

Read real-world advice from Wi-Fi wizard Glenn Fleishman on setting up a wireless network using Apple's 802.11n and 802.11ac base stations. Learn to maximize performance, extend range, connect multiple base stations, handle complex configs, share USB disks and printers, and more.


Try productivity tools from Smile that will make your job easier!
PDFpen: PDF toolkit for busy pros on Mac, iPhone, and iPad.
TextExpander: Your shortcut to accurate writing on Mac, Windows,
and iOS. Free trials and friendly support. <>

Comments about Use Time Machine with the 802.11ac AirPort Extreme Base Station
(Comments are closed.)

Alan Forkosh  An apple icon for a TidBITS Supporter 2013-12-03 19:07
I picked up one of new Extemes on Black Friday (Apple messed up the gift card, so I'm getting an actual credit!). Anyway, I've hooked up a a portable 1TB drive that I'm not currently using and will check it out as a second ™ for my main Mac (currently with 800GB of data).

I'll try to remember to report progress.
Stanton  2013-12-03 20:57
It's working fine for me with a several-years-old Iomega Prestige USB drive. It was recognized immediately by the base station without further configuration. Just had to select it in Time Machine preferences on the Mac side. I wasn't sure whether I would have to power it independently of the base station, but it's working fine using the bus power provided by the base station. Couldn't be simpler.
I'm trying to understand the original issue: officially supported or not, I've been backing up my Mountain Lion (and Lion, and Snow Leopard before that) MacBook Pro using timemachine to a USB HD connected to my dual-band Airport Station (4th gen) for a few years already, and I've implemented this setup at a number of clients. I've also attached a USB drive as secondary backup storage to earlier time capsules. Did I miss something?
Adam Engst  An apple icon for a TidBITS Staffer 2013-12-04 07:40
It has been possible since day one, but has always officially unsupported, and Apple recommends against it, because many people have found it unreliable. That's what has changed with the new 802.11ac base station.
ljwink  2013-12-10 04:37
'officially unsupported' or not, it has always works flawlessly for me with a similar configuration since Leopard.

See .
Don't really understand the issue...I currently use a 1T external drive hooked into my iMAC running Snow Lepoard -via Time Machine. Same thing with my MACBook...I never figured out how to hook up to my AirPort Extreme, so this is what I use.

I was told when I bought my iPad, I could use the AirPort Extreme to back to iCloud (don't know if that works, cuz I don't understand how that could be). I back up the iPad to the MacBook & back that up via Time Machine....
Adam Engst  An apple icon for a TidBITS Staffer 2013-12-04 13:56
Connecting an external disk to a Mac to back up via Time Machine works fine, of course, but it may not be as convenient (particularly for a MacBook) as having the drive be connected to the AirPort Extreme Base Station. As noted in the article, Apple promised this feature in Leopard betas, and then claimed that it was unsupported until the release of the 802.11ac AirPort Extreme in June 2013.
Jim Saklad  2013-12-04 14:18
My Retina MBPro can talk to the new Airport Base Station using 802.11ac -- very fast.
The Base Station can only talk to a TM drive using USB-2 -- NOT so fast.
What sort of real-world backup data transfer speeds do people see with such an arrangement?
Adam Engst  An apple icon for a TidBITS Staffer 2013-12-04 14:28
I'm not sure they're all that different. Apple's implementation of 802.11ac is technically capable of 1.3 Gbps, and USB 2.0 does only 480 Mbps. But the real-world throughput of 802.11ac is likely 30-60 percent lower, which brings them much more into line.

That said, your point is well taken, and Apple would do well to move to USB 3.
Jim Saklad  2013-12-04 16:53
Apple sells 2 iMacs, 2 Macbook Airs, and 2 Macbook Pros with 802.11ac -- all of which have USB-3. They also brought out this same year 2 Wifi devices (a Base Station and a Time Capsule) with 802.11ac, but these both have USB-2.

Brent York  2013-12-04 17:29
I backed up to a HDD connected to an AE a few years ago but learned it may see it and back up to it, but the restoring from it-the crucial part of being able to get your data, may not work. The guys at Mac Geek Gab warned me of this.
David Price  An apple icon for a TidBITS Supporter 2013-12-05 00:44
This is great news! Anyone who has tried to rebuild a disk from a Time Capsule knows how dang slow it is. Restoring via wifi is hopeless and restoring via the Ethernet port isn't much better. It appears that now the Time Machine backup disk can be easily disconnected from the AirPort Extreme and directly connected to the Mac target for a fast restore.
Adam Engst  An apple icon for a TidBITS Staffer 2013-12-05 07:50
That's good to hear - I've been wondering how this would all work in the real world, given that 802.11ac and Gigabit Ethernet (if the Mac is directly connected to the AEBS) should be at least somewhat faster than USB 2.0. But as a previous commenter noted, newer Macs have USB 3.0, which maxes out at 5 Gbps. That might point to buying a USB 3.0-capable drive, seeding the initial backup to it, moving it to the AEBS for normal use, and bringing it back local if you need to do a full restore. I imagine there are devils in those details, but it's nice in theory.
Scott Randolph  2013-12-07 14:06
I'm backing up to an Extreme connected USB drive using both Time Macine and CrashPlan. With CrashPlan I have to wake the hard drive up by selecting it through Finder. Time Macine seems to wake the hard drive up itself although not 100% of the time.
Steve L'Heureux  2013-12-09 19:25
Ok, well big whoop. When will Apple have the common sense to make the Time Machine Backup bootable AND get all files backed up and not leave people wondering what happened to their Calendar or other "orphaned" essentials? Until that day (and likely longer), I'm all about Carbon Copy Cloner. It works flawlessly.
barefootguru  An apple icon for a TidBITS Contributor 2013-12-10 00:42
You can boot your Mac from the emergency partition and immediately restore from a Time Machine backup: TM backs up everything except cache files which will be recreated the next time they're needed, so don't know why you're spreading FUD.
Tom Harrington  2014-01-03 15:01
It looks like the reference to Airport Extreme has been deleted from the "Mac Basics" support article. It now says you can use " external drive (sold separately) or AirPort Time Capsule." The Airport Extreme manual still says Time Machine is OK, but the change in the support article makes me wonder. I used Time Machine over my network to a hard drive on another Mac for years without issues, but within a week of moving the hard drive to an Airport Extreme I got the dreaded "Time Machine must create a new backup for you" message.
Adam Engst  An apple icon for a TidBITS Staffer 2014-01-04 16:18
I'm still seeing the mention in the Mac Basics document - it's hidden under the Choosing a Backup Drive section. I really dislike how Apple's support documents hide information like this now - you have to Expand All to make sure you can read the entire thing.

"Time Machine can only back up to a external drive connected to an AirPort Extreme 802.11ac base station. Time Machine cannot back up data to external drives connected to other AirPort Extreme base station models."
Tom Harrington  2014-01-05 22:13
Hmm, I see, it's definitely well buried on the page. I guess it's supposed to work, though I'm still trying to puzzle out why my backup scheme has gone completely to hell since I switched to using an Extreme for backups. I'm at my third "verifying backup" of the day on one Mac and the second "the identity of the backup disk has changed" today on another.
Adam Engst  An apple icon for a TidBITS Staffer 2014-01-06 07:18
That's distressing - it might be worth calling Apple now that it's a supported configuration.