Advice for backing up iCloud Photo Library

Hi All - I’d love some advice on backing up my photo library that is currently on iCloud Photo Library. My MacBook Pro SSD is unfortunately too small to hold all my originals, and because it is a laptop it is neither always on nor always plugged in. I’ve read a lot of the other posts on the forums here (for example here). But there are some conflicting pieces of advice, so I wanted to follow up.

My first idea was to get a Synology and move my photo library to the Synology, but Apple’s KB on the topic seems to discourage that idea. So the next idea was to attach an external drive to my laptop, move my photo library to an external drive, set that library to be the “System Library,” and turn on “Download Originals” to that drive. But that led to several questions:

  1. Some people on the MPU Forums have said that iCloud Photo Library only works on a local drive, does that include an external drive physically attached to the computer?
  2. As long as I don’t open the Photos app on the laptop when the drive isn’t connected, are there any issues with storing the Photo library on an external drive?
  3. If I only connect the laptop to the external drive every few weeks, is that going to create issues with syncing?

It’s clear to me that the easiest (and most expensive) approach would be to have a Mac mini or other desktop Mac, attach external storage to that Mac, and have the originals stored there. I’m not opposed to that option, but I’d ideally like to find a fairly robust way to backup my photos without needing to buy a whole new Mac…

Thanks for the help!

Works fine on an external drive. I have my Photos library on an external SSD attached to my Mac Mini.

If you try to open when the external drive is not attached, the Mac OS will tell you it can’t find the Photos library and will give you a chance to quit or open another library.

I think it that when you reconnect your external HD it just resumes synching as normal. See what others on this forum think about this one.

Also, synching your Photos library (downloading all originals to external HD) is not backing up. It does give you the opportunity to back up the entire Photos library to a cloud service, another HD, etc.


I think you meant “ If you try to open when the external drive is not attached, the Mac OS will tell you it can’t find the Photos library…“ Other than that, I concur.

Thank you so much. I will have a talk with my proofreader. I have fixed this in my original reply to the OP.

Totally agreed - what I didn’t say in my original post is that my main goal with all of this is to be able to actually create a backup. Once I have all my originals downloaded somewhere, then I can have a Time Machine backup that includes those images and set up a Backblaze account that can duplicate those files remotely.

Part of the reason why I may still lean towards a Mac Mini with an external attached drive is because I think I could attach a large drive with different partitions that would simultaneously:

  • Hold all original photos
  • Serve as a networked drive for my Time Machine backup from my MBP
  • Serve as Time Machine backup for the Mac Mini
  • Serve as a networked drive for my wife’s Windows laptop to backup to

And the Mac Mini could run Backblaze all the time, including the physical attached drive, without me having to remember to turn on my MBP, connect the external drive, sync new photos, run Backblaze, etc. Even that’s not ideal because it’s putting a lot of eggs in a single local drive basket (with Backblaze as the backstop)… but one thing at a time :smiley:

I really like the convenience of having an always-on Mac Mini. It is my daily work machine. I don’t have a laptop. I have a few external SSDs with my music, photos, documents, etc. I also have an external 4GB spinning HD just for Time Machine.

Apple says a Photos library on an external disc can use iCloud Photos, if that lib is designated as the System Photo Library.

I think the reason a Synology (or other NAS) isn’t considered a good option for primary storage of a Photos library is that Apple says in the article footnote, the disc must be formatted APFS or Mac OS Extended (Journaled). I’ve heard a workaround for that is iSCSI on the NAS, but it seems sketchy and unsupported.

I’m in the same boat. Photos are a nightmare with a MacBook, because the library is supposed to be internal or directly attached, both of which are difficult on a laptop, especially as the library only grows over time. I wish Apple offered a NAS, but they seem to push iCloud instead, but to me that’s really just sync to other devices. It can’t be the primary storage, because it can’t be backed up, unless the MacBook has the entire library anyway. So frustrating.

Apple’s answer of course is offloading your image storage to iCloud Photos. But nothing requires you to always have access to all your photos in the cloud at a moment’s notice.

Also, you can easily have multiple libraries, and merge to a larger external drive’s library when desired. And you don’t even need to live in side the Apple ecosystem. There are also plenty of 3rd-party options, free to pricey, from Google Photos to Lightroom CC (which a 1Tb storage plan for $9.99/month). Apple has never condescended to coding its apps to directly support NASes. :man_shrugging:

That’s confusing the issue. The filesystem of the client is unrelated to the filesystem of the server. File sharing on the Synology use the SMB protocol with is totally independent from the file system. You cannot direct-connect an APFS drive to a Synology drive but you certainly can transparently transfer images back and forth without issue.

I have tens of thousands of images split between Photos and Lightroom Classic, and I barely use any cloud sync at all. I connect my phone and my camera SD cards periodically and offload images to my Mac, and maintain, manage and back up everything locally and with BackBlaze. If I had a NAS it wouldn’t much different much more difficult.

Apple’s answer of course is offloading your image storage to iCloud Photos.

Hmm, I don’t see iCloud as viable “offloading” because I want the full library backed up properly (existing somewhere other than just iCloud). For that, it needs to be on my Macbook, or a local an external/nas, or Mac Mini, from which it can be included it in backups via Time Machine, Backblaze/Arq, Carbon Copy Cloner).

nothing requires you to always have access to all your photos in the cloud at a moment’s notice

I totally agree, and I have no interest in “always access” to all my photos, which to me is the main promise of iCloud Photos.

Google Photos

This has the same problem as iCloud… it’s not an offload, because the entire photo library still needs to be local, for it to be backed up.

That’s confusing the issue. The filesystem of the client is unrelated to the filesystem of the server.

I don’t have a NAS, and this is getting over my head. I was just quoting from an Apple support doc titled “Move your Photos library to save space on your Mac”, which seems to say that the external disc must be APFS or HFS+.

Not if you’re using a NAS.

So don’t use it! I don’t, just as I don’t use Time Machine or Pages.

To parse the problem in more depth:

First, the tech note in question doesn’t recommend a managed library on a NAS:

To prevent data loss, Apple doesn’t recommend storing photo libraries on external storage devices like SD cards and USB flash drives, or drives that are shared on a network.

Why, one wonders? To quote from “Take Control of Your Digital Storage”, pp. 109-110:

The short answer to the question of how to use Apple’s Photos app with a NAS is: you don’t. Here’s why:

  • Photos stores everything in a central library file (a package, like Lightroom uses), which includes original image files, thumbnails, metadata, and more. Storing that file on a NAS risks corrupting the library if the volume drops or there’s a hiccup in the network while data is being written.

This logic perhaps also extends to the idea of using, e.g., iscsi targets or sparse images on a NAS … seems like it should work, until some transfer glitch in the network corrupts the container.

Edit: here’s another explanation, this time from the FAQ for the open-source DAM and photo editor called DigiKam:

However, and second, if you want, you can do what bowline alludes to, which applies to any external volume, including a NAS (continuing from “Take Control”):

• There is a method of adding images to a Photos library so the originals are not located in the master library file (see just ahead), but if you use iCloud Photo Library, they won’t be synced through iCloud and made available to your other Apple devices. Only images stored within the library file on the startup disk can be synced with iCloud Photo Library.

This is sometimes called a referenced library. That is, you can store the original images on the NAS, and use (or another program like Lightroom, or Capture One) as the organizer – the original files therefore reside outside of the library package. But it is important to underscore, in the case of, these photos will not be synched to iCloud and other Apple devices, and of course you have to have a scheme to back up the external drive or NAS.

1 Like

I’ve been using an external SSD as primary Photos library with my MBP as others are talking about and it has been just fine. What I would add is that I also have run clones of that library to 2 other external drives (using Carbon Copy Cloner) every time I add new photos the primary library, so I can rotate these clones between my office and home (hence 2 copies at home, 1 in a different physical location). I tested one the clones again the other day (plugged into MBP and opened Photos from that library) and it worked just fine.

My experience with having my iCloud Photo library on an external drive on my laptop has been kind of hellish, mainly because of the combination of two factors:

  1. Having the iCloud Photo Library in an external drive can corrupt the library if the drive is not properly ejected.
  2. When Photos is not running, there is the dreaded “photoanalysisd” process analyzing all your library on the external drive, so it cannot be unmounted.

To make things worse, using my monitor (LG UK850-W) as an USB hub has the effect that if the monitor goes to sleep, the hub gets
unpowered, so its as if the drive was disconnected.

I cannot count the times I’ve ended with a corrupted library and had to download everything again.

Safest thing: having an always on Mac Mini with a 1TB magnetic drive for Photos, on the laptop I’ve given away.

You can use the command below to stop mediaanalysisd from running. I have not noticed any issues with the service not running. I keep my photo library on an external SSD and should I need to unmonitored the drive it happens instantly.

launchctl unload -w /System/Library/LaunchAgents/