How to migrate data from a 1TB 2018 Mini to a 512 GB M4 Mini with an external SSD

[Matz]

Ok, I've searched for this particular situation, and have not found what I need. Maybe I'm missing something simple here. Don't know.

The situation:

Early this morning I began the setup of my new M4 Mini, 512 GB, with a 2 TB Thunderbolt external SSD from OWC.

My old Mini is a 2020 refresh of the 2018 Mini, with 1 TB and 32 GB of RAM.

The data from the old Mini won't fit on the new Mini's smaller SSD. Hence, the external SSD.

The largest portion of the data is photos; roughly 65GB. I assumed that would go on the external drive.

My old Mini is backed up on two external hard drives, via USB-A. I have two partitions on each drive, used exclusively for backups; one with SuperDuper, the other with Time Machine.

Since I only have one monitor, I honestly couldn't grasp how to manage the migration without being able to have both Minis up and running. Then I read a post on an Apple forum somewhere that I could migrate the data by restoring from a Time Machine backup from the old Mini to the new Mini. Seemed worth a try, so I hooked up the two backup drives to the new Mini, hooked it up to the monitor, and went through the prompts to set it up.

When I got to the point of choosing a data source for the migration, I picked one of my two Time Machine backups, opened up the most recent backup, and the Restore button was greyed out. I waited, and waited; still greyed out. So I gave up on that.

In the meantime, my iCloud files were automatically populating the new Mini. A few hours later, it appears that all of my texts, emails, and documents are on the new Mini's internal SSD.

I dragged my Photos library file over to the external SSD, and set it as the System Photos Library. The photos are still downloading some hours later, but they're now where they belong.

I also downloaded various apps that weren't in iCloud. Not a big deal, but not without incident. For example, I can't access my Microsoft 360 subscription for Word and Excel. Not good. The subscription shows up in my Apple account, but when I open Word or Excel, and try to restore a purchase, it says I don't have a subscription. Huh.

Hopefully a phone call or a chat tomorrow with Apple will fix that.

In the meantime, I'm wondering what else I'm missing by not being able to use Migration Assistant. And how the heck is it supposed to work with two headless Macs and only one monitor? Again, maybe I'm missing something basic. Wouldn't be the first time.

Maybe it's fine. I'm just not sure. Any constructive thoughts on this would be appreciated.

Thanks.

 

[velocityg4]

If you can redownload apps and settings on the computer and just need data in your user files. If just plug the SSD into the old computer and copy them.

Then plug into the new one. Create shortcuts and move what you want in the external. Link any apps on the new computer to the correct databases or folders. Such as Photos to the photo database, setting download folders in Chrome or OneDrive location in OneDrive.

Alternatively, just copy the files you plan on storing in the SSD to the SSD and delete from your old Mac. Update your backup then run Migration assistant. Do any other linking to the SSD file locations as previously mentioned.

 

[Bigwaff]

I waited, and waited; still greyed out. So I gave up on that.

How long did you wait? HDD slow. Migration Assistant has to take inventory and this take time when there are history of backups on disk. Latest backup will not have all files, only latest changes.

 

[Matz]

If you can redownload apps and settings on the computer and just need data in your user files. If just plug the SSD into the old computer and copy them.

Then plug into the new one. Create shortcuts and move what you want in the external. Link any apps on the new computer to the correct databases or folders. Such as Photos to the photo database, setting download folders in Chrome or OneDrive location in OneDrive.

Alternatively, just copy the files you plan on storing in the SSD to the SSD and delete from your old Mac. Update your backup then run Migration assistant. Do any other linking to the SSD file locations as previously mentioned.

Thanks. That's a thought, although it's looking like I may be past that point. I'm going to let the photo library finish downloading tonight. There may be a straggler or two, but I think I have all of the apps. It's just a matter of doing whatever with each one because they're on a different machine now, and as a result some need a serial number, key, or something else that isn't stored in Passwords.

Plus, as I reinstall the paid apps and even some of Apple's included apps, I'll have to decide where each one goes, based on size. It's a pain, but one that I don't see a way to avoid, given that the two Minis differ in storage volume and configuration.

As for the system files, the Mini downloaded 15.2 shortly after plugging in; my 2018 is 15.2; so we're good. All of that resides on the Mini's internal SSD. It's a clean install. And much as it pained me to pay so much for so little storage, I think I'm going to be glad I went for 512 GB.

 

[Matz]

How long did you wait? HDD slow. Migration Assistant has to take inventory and this take time when there are history of backups on disk. Latest backup will not have all files, only latest changes.

Probably not long enough. I got impatient. It took awhile before all four drive images appeared, maybe twenty minutes or longer; and waiting on Time Machine took quite a bit longer than that.

As mentioned above, iCloud is working pretty well. I could try a restore from the SuperDuper bootable backup, but now am leaning towards a clean install as being a good thing. There are some apps I haven't used in a year or longer; it's probably safe to get rid of them. Time for housecleaning.

 

[tonmischa]

Several issues here, I will only address two of them:

1. Migration Assistant will only migrate a) personal data that is inside your User folder, b) Apps that are inside your Application folder and c) some system-wide settings. It will NOT migrate any data that is stored outside of these folders (for example on a different partition or external drive.)
(You did not mention specifically where your "old" data was located, so I am just making sure.)

2. One-Monitor problem:
- Connect Monitor and Mouse to your old Mac. Start Migration Assistent, select "to another Mac" and continue up to the point where the Mac is waiting to be connected to.
- Now connect Monitor and Mouse to the new Mac, start Migration Assistant, select "from another Mac", it should show the old Mac. Select it. It will eventually ask you to confirm a number.
- Connect Monitor and Mouse to the old Mac. Confirm the number.
- Connect Monitor and Mouse to the new Mac. Watch the migration run. When it finishes, follow the instructions until the account is completely set up. (=you can see the Finder.)
- Connect Monitor and Mouse to the old Mac. Quit Migration Assistant and Shutdown.
- Connect Monitor and Mouse to the new Mac. Enjoy.

I usually put the new Mac on top of the old Mac, so the connection switch can be done very easily.

EDIT:
3. I have to ask:
You say 512 GB on your new Mac is not enough space for your data.
But you also say: The largest portion of your data is a 65 GB Photos library. (Which I understand to mean that all your other data (everything minus the Photos library) is smaller than 65 GB. So it is less than 130 GB in total).
What am I missing here?

 

[Matz]

Several issues here, I will only address two of them:

1. Migration Assistant will only migrate a) personal data that is inside your User folder, b) Apps that are inside your Application folder and c) some system-wide settings. It will NOT migrate any personal data that is stored outside of these folders (for example on a different partition or external drive.)
(You did not mention specifically where your data was located, so I am just making sure.)

2. One-Monitor problem:
- Connect Monitor and Mouse to your old Mac. Start Migration Assistent, select "to another Mac" and continue up to the point where the Mac is waiting to be connected to.
- Now connect Monitor and Mouse to the new Mac, start Migration Assistant, select "from another Mac", it should show the old Mac. Select it. It will eventually ask you to confirm a number.
- Connect Monitor and Mouse to the old Mac. Confirm the number.
- Connect Monitor and Mouse to the new Mac. Watch the migration run. When it finishes, follow the instructions until the account is completely set up. (=you can see the Finder.)
- Connect Monitor and Mouse to the old Mac. Quit Migration Assistant and Shutdown.
- Connect Monitor and Mouse to the new Mac. Enjoy.

I usually put the new Mac on top of the old Mac, so the connection switch can be done very easily

1. Good to know. The data on the old Mac is on its internal SSD. Its external HDDs are only for backups.

2. That sounds like a good way to use the single monitor between the two Minis. I just might do that tomorrow.

Thanks.

 

[Matz]

EDIT:
3. I have to ask:
You say 512 GB on your new Mac is not enough space for your data.
But you also say: The largest portion of your data is a 65 GB Photos library. (Which I understand to mean that all your other data (everything minus the Photos library) is smaller than 65 GB. So it is less than 130 GB in total).
What am I missing here?

That 65 GB figure was wildly incorrect. As it turns out, as of this writing the Photos Library is actually 165GB and growing. My apologies for the confusion.

What I discovered through this process is that I've been storing my Photos Library on iCloud, without realizing it. Not sure when that happened, but it was a surprise to me. As a result, the Photos Library on the old Mac appeared to be much smaller than it actually was.

Looking back, according to the bootable backup, the old Mac's 1 TB internal drive held a total of ~630GB of data, including a 35GB Photos Library, and was growing. My concern was that 1 TB would be insufficient in the not too far distant future, so I opted for a 2TB external Thunderbolt 4 drive to avoid paying Apple's crazy storage prices while still having reasonable r/w speed and some room to grow.

At the last minute I decided to upgrade to 512GB internal storage, so as to have a bit more room for system files and those apps and data that would benefit from being on internal storage. I still think that was a reasonable decision.

The original photos are continuing to download to the external drive on the new Mac, as I want all of them stored and backed up locally. It's taking up a whole lot more space than I had thought.

Again, sorry for the confusion.

 

[TheRealAlex]

Ok, I've searched for this particular situation, and have not found what I need. Maybe I'm missing something simple here. Don't know.

The situation:

Early this morning I began the setup of my new M4 Mini, 512 GB, with a 2 TB Thunderbolt external SSD from OWC.

My old Mini is a 2020 refresh of the 2018 Mini, with 1 TB and 32 GB of RAM.

The data from the old Mini won't fit on the new Mini's smaller SSD. Hence, the external SSD.

The largest portion of the data is photos; roughly 65GB. I assumed that would go on the external drive.

My old Mini is backed up on two external hard drives, via USB-A. I have two partitions on each drive, used exclusively for backups; one with SuperDuper, the other with Time Machine.

Since I only have one monitor, I honestly couldn't grasp how to manage the migration without being able to have both Minis up and running. Then I read a post on an Apple forum somewhere that I could migrate the data by restoring from a Time Machine backup from the old Mini to the new Mini. Seemed worth a try, so I hooked up the two backup drives to the new Mini, hooked it up to the monitor, and went through the prompts to set it up.

When I got to the point of choosing a data source for the migration, I picked one of my two Time Machine backups, opened up the most recent backup, and the Restore button was greyed out. I waited, and waited; still greyed out. So I gave up on that.

In the meantime, my iCloud files were automatically populating the new Mini. A few hours later, it appears that all of my texts, emails, and documents are on the new Mini's internal SSD.

I dragged my Photos library file over to the external SSD, and set it as the System Photos Library. The photos are still downloading some hours later, but they're now where they belong.

I also downloaded various apps that weren't in iCloud. Not a big deal, but not without incident. For example, I can't access my Microsoft 360 subscription for Word and Excel. Not good. The subscription shows up in my Apple account, but when I open Word or Excel, and try to restore a purchase, it says I don't have a subscription. Huh.

Hopefully a phone call or a chat tomorrow with Apple will fix that.

In the meantime, I'm wondering what else I'm missing by not being able to use Migration Assistant. And how the heck is it supposed to work with two headless Macs and only one monitor? Again, maybe I'm missing something basic. Wouldn't be the first time.

Maybe it's fine. I'm just not sure. Any constructive thoughts on this would be appreciated.

Thanks.

Recently had this issue myself.

Used external Thunderbolt Crucial X10 2TB
Created a New Album on my M4 Pro Mini
Then dragged that new Album to my external X10 drive
Took a while but all 6,500 files are there.

 

[Fishrrman]

The OP's adventures above is why I NEVER recommend trying to "downsize" from an older Mac to a new one with a smaller internal drive.

The new Mac's drive should be at least the same size as the one you're migrating "from".

Actually, it prompted ...
Fishrrman's "Mac Rule Number 8":
On any new Mac, the internal drive should be 2x the size of the Mac which it is replacing.
Otherwise, there will be problems in the future as the needs of the OS grow...

 

[Matz]

The OP's adventures above is why I NEVER recommend trying to "downsize" from an older Mac to a new one with a smaller internal drive.

The new Mac's drive should be at least the same size as the one you're migrating "from".

Actually, it prompted ...
Fishrrman's "Mac Rule Number 8":
On any new Mac, the internal drive should be 2x the size of the Mac which it is replacing.
Otherwise, there will be problems in the future as the needs of the OS grow...

Please see my last statement in the OP:

Any constructive thoughts on this would be appreciated.

Thanks for your concern.

 

[tonmischa]

Again, sorry for the confusion.

No worries.

In case you are still looking for an opinion:
I think you have two options here, which both have advantages and disadvantages.

1. Start over and use Migration Assistant
Advantages: Your system will (hopefully) run exactly the same as on your old Mac. (App Licences, Office Subscriptions, Mail accounts, and so on)
Disadvantage: You have to start over. Also: You will have to sort through the stuff on your old Mac to bring the Data Sizes down to <512 GB. (e.g. moving the Photos library over manually to the external SSD.)
* I am deliberately ignoring the fact that a lot of photos are/were stored in iCloud.

2. Go ahead with the approach you already started.
Advantage: You seem to have made good progress. Stuff is downloading, everything is in its desired place. A few kinks have to be ironed out (Office subscriptions), but this can hopefully be solved with a call to Apple Support. You already mentioned, that a "clean install" is a good idea (I agree!).
Disadvantage: You have to check for everything manually. And sometimes it will take months to realize that one very important document is missing. (But: You seem to have a good backup strategy, so this will probably not be a big problem.)

From what I can gather, I would recommend going ahead with option 2.
Good luck!

 

[Matz]

No worries.

In case you are still looking for an opinion:
I think you have two options here, which both have advantages and disadvantages.

1. Start over and use Migration Assistant
Advantages: Your system will (hopefully) run exactly the same as on your old Mac. (App Licences, Office Subscriptions, Mail accounts, and so on)
Disadvantage: You have to start over. Also: You will have to sort through the stuff on your old Mac to bring the Data Sizes down to <512 GB. (e.g. moving the Photos library over manually to the external SSD.)
* I am deliberately ignoring the fact that a lot of photos are/were stored in iCloud.

2. Go ahead with the approach you already started.
Advantage: You seem to have made good progress. Stuff is downloading, everything is in its desired place. A few kinks have to be ironed out (Office subscriptions), but this can hopefully be solved with a call to Apple Support. You already mentioned, that a "clean install" is a good idea (I agree!).
Disadvantage: You have to check for everything manually. And sometimes it will take months to realize that one very important document is missing. (But: You seem to have a good backup strategy, so this will probably not be a big problem.)

From what I can gather, I would recommend going ahead with option 2.
Good luck!

Thank you. Your suggestions and comments have been helpful.

I’m going with option 2, for the reasons you gave. The kinks do seem to be working out. A couple of hours ago I managed to resolve the problem with Office, Fantastical, and a couple of other apps. All are functioning normally now.

The Photos Library has finished downloading to the external drive, and it is about 165GB. Whew.

All of my documents appear to be present, and in their proper places.

As a precaution, my thought is to keep one of the two backup HDDs intact, and use the other HDD for my new Mac’s SuperDuper and Time Machine backups. That way I can go back to the untouched backups if need be.

That said, it might be reasonable to explore some faster backup drives, as restoring a backup from one of these spinning hard drives is, as @Bigwaff pointed out, slow. Slower than I had imagined.

Again, thanks for your help.

 

[Matz]

No worries.

In case you are still looking for an opinion:
I think you have two options here, which both have advantages and disadvantages.

1. Start over and use Migration Assistant
Advantages: Your system will (hopefully) run exactly the same as on your old Mac. (App Licences, Office Subscriptions, Mail accounts, and so on)
Disadvantage: You have to start over. Also: You will have to sort through the stuff on your old Mac to bring the Data Sizes down to <512 GB. (e.g. moving the Photos library over manually to the external SSD.)
* I am deliberately ignoring the fact that a lot of photos are/were stored in iCloud.

2. Go ahead with the approach you already started.
Advantage: You seem to have made good progress. Stuff is downloading, everything is in its desired place. A few kinks have to be ironed out (Office subscriptions), but this can hopefully be solved with a call to Apple Support. You already mentioned, that a "clean install" is a good idea (I agree!).
Disadvantage: You have to check for everything manually. And sometimes it will take months to realize that one very important document is missing. (But: You seem to have a good backup strategy, so this will probably not be a big problem.)

From what I can gather, I would recommend going ahead with option 2.
Good luck!

An update:

After further thought, I decided to go back and implement option 1; mainly because one of my key apps - Google Earth - wasn't functioning properly. As a landman, I find GE to be incredibly useful in my work, and have added a lot of kmz files to make it even more useful. I didn't see any way to easily and cleanly migrate all of that data to the new Mac using option 2.

Thanks to your instructions for using a single monitor with two Minis, I was able to work through the migration in fairly short order. I used an ethernet cable to effect the transfer, but found out that I could have used a Thunderbolt cable, which might have been faster. The whole thing took less than an hour.

Again, the new Mini's internal drive being smaller than the old one forced me to choose which data to migrate. Turned out that I had enough space for all of the critical data, thanks to having a 512GB drive. There were a few odds and ends to clean up afterwards, such as enabling my Apple Watch to unlock the Mini, plus a couple of iCloud settings, but now it's just like my old Mini, only much quicker.

Success!

 

[Matz]

Another update:

After using the new M4 Mini for about two months, I'm finding that the 16GB of memory gets used up more often than I had expected. Even with AI turned off, I often have only 5 GB of free memory, and things seem to slow down noticeably.

Although I don't do any coding, video editing, gaming, or other intensive uses, I routinely have a number of apps open at the same time: Mail, Excel, Word, Safari, Google Earth, Messages, and sometimes Photos. When watching youtube videos, I experience lags. Websites in Safari sometimes are slow to load completely, especially pictures. So I'm finding that for my day to day use, 16GB isn't quite optimal.

Sure, I could open and close apps to preserve memory, but it's more convenient for my workflow as a consultant to keep those apps open. I dislike having to constantly monitor it.

So I'm thinking seriously of sending it back, as it's within the 90 day return for Costco, and ordering a new Mini with 24GB of RAM from Apple. I don't know that I need 32GB, but input is welcome.

As for storage, it seems to be handled pretty well by the 2TB external SSD, but that setup does have its drawbacks. To @Fishrrman 's point (which now appears to have been correct, thank you), while I'm at it I'll increase the internal storage to 1TB. 2TB would be nice, but that's pushing the limits of my willingness to spend. We'll see.

The OWC 2TB external SSD would get partitioned as a backup drive, for SuperDuper and Time Machine. My old USB-A HDDs are just too slow. I'd probably buy an additional 2TB SSD so as to have two backup drives, and retire the HDDs.

I've been looking at other Macs, but none of them delivers the performance of the Mini at a similar price, even with upgraded RAM and internal storage. I don't want or need a laptop, nor do I want an iMac. So the Mini seems to be it.

This is definitely not where I expected to be. It appears that my choice was not a good one for my situation. Such is life. Fortunately I have a few days to decide before the return window closes. With full credit for my 512GB Mini, the additional cost of upgrades would seem to be worth it; particularly in the long run.

So that's where I'm at.

 

[Matz]

Done. The new M4 Mini 64GB 1TB is supposed to arrive in early March.

 

[bjsr]

I have read this thread with interest because I have a similar situation and was looking for a solution. My 3T iMac (not full) crashed in September (long sad story over several months of attempting to resurrect it). I did NOT want to downgrade 3T to 512 GB nor a smaller screen size to the new iMac which was still 512....,or keep everything on SSD (I do use a 5T backup with time machine). I also sync iPhone AND MacBook Pro to access everything away from my desk, using iCloud. It has worked wonderfully for me for years. I was assured the 512 would be adequate. I didn't think so but they are the experts, right?

After several days and phone calls to Apple trying to put it all on the Mini unsuccessfully, I was told to go to Genius Bar, so off I went an hour later...and was told I needed a 1T ($200 more)...That was the only way to have access to everything. We bit the bullet and paid $600 more for the 2T after returning the 512 (with 4 days to spare on the 14 day policy).

I am still baffled WHY I was told the 512 would work....my pictures alone were also in the 165 GB range, but I thought it was from iCloud, not the computer itself. They said something about the original footprint backup (back in 2017?) wouldn't fit on the mini..I get it, but WHY haven't they made a larger mini??? It makes no sense to me unless there is a way to access all data remotely. People should be given better information. I never liked the option of a smaller Mini, but didn't see a better option with Apple. (it is $$$$ especially after getting the studio monitor).