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pixxelpusher

macrumors member
Original poster
Aug 1, 2011
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Since migrating to my new M1 Max MacBook Pro from my old 2014 MacBook Pro Time Machine won't associate the old backups to the new computer.

I have years of backups and the computers have the same names, but Time Machine simply won't pick up from where I left off, it always wants to do a completely new full backup.

I have read to delete the new backups and use Terminal to inherit the drive and then associate the old backups, but it doesn't work it just keeps doing a fresh full backup.

I've tried multiple ways to write the associate code but Terminal always gives an error of either "A local volume mount point and a snapshot volume path are required" or "Not a snapshot volume".

The old MacBook Pro was running MacOS 10.14.6 and new one is running latest 12.2.1

Has anyone achieved this and if so how? any advice or steps would be appreciated.
 
Hmm this is pretty much what I expected.
I have my old iMac backing-up daily to a 4TB HDD, but I fully expected that, after restoring my documents and apps to a new M# computer, I'll have to start all over again.
I had even though of buying a new 4TB HDD and not touching the old one again after the transition, just keep it as a permanent snapshot as at dd/mm/yyyy, so that in the unlikely event I do have to reach back further than the date of the last iMac backup, I can do so.
 
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Not sure if you have tried tmutil for this. So information at: https://simon.heimlicher.com/articles/time-machine-inherit-backup-using-tmutil/

sudo tmutil associatedisk -a "/Volumes/Macintosh HD" "/Volumes/Time Machine Disk/Backups.backupdb/John Doe's MacBook/Latest/Macintosh HD"
Thanks, yes like I mentioned I've tried all methods I can find to associate the drive in Terminal:

sudo tmutil associatedisk -a /

sudo tmutil associatedisk -a "/Volumes/NameDiskB" "/Volumes/NameBackupDrive/Backups.backupdb/ComputerName/Latest/NameDiskA"

for f in /Volumes/TimeMachine/Backups.backupdb/YourBackupComputer*; do if [[ -d "$f" ]]; then sudo tmutil associatedisk /Volumes/MacintoshHD "$f"/MacintoshHD; fi; done

I've never had this problem in the past as I've migrated a few MacBook Pro's and they have always associated properly to the old backups and just done a partial backup. This meant I could scroll back through my entire history for files. But I can't do that now and just get that odd "snapshot" message.

I feel like something is still broken in Monterey Time Machine
 
Hmm this is pretty much what I expected.
I have my old iMac backing-up daily to a 4TB HDD, but I fully expected that, after restoring my documents and apps to a new M# computer, I'll have to start all over again.
I had even though of buying a new 4TB HDD and not touching the old one again after the transition, just keep it as a permanent snapshot as at dd/mm/yyyy, so that in the unlikely event I do have to reach back further than the date of the last iMac backup, I can do so.

Why would you expect this? When you fully migrate Time Machine is supposed to associate the old backup to the new machine and just backup the changes like before. I've migrated from a few MacBook Pros over the years and it has always continued on. I've always been able to just scroll through my backup history, but now I can't as it's created a whole new computer (meaning I've basically got 2 computers that are pretty much the same taking up 2x the space).

But it did "Inherit" the old backup, so they are all in the same folder. But just recognized as different drives.

Also I always have another drive attached for storage and it's done the same thing for that as well, so it has 2x that drive as well (It's labeled the new backup with a "1" on it). This is really odd to me.

What I have noticed though is that the new backup it's made is simply called "Data" and not my actual hard drive which is "MKBK" so it's not connecting the old and new together at all.
 
Things have changed quite a bit since Mojave. Starting with Catalina, the Mac's HD is split into two volumes. "Macintosh HD" is basically the read-only OS volume and does not get backed up anymore, and the "Macintosh HD - Data" volume is where your data lives and gets backed up. So I think it makes sense you are seeing a backup called "Data".

More info:

If you do it through the Time Machine UI, does it ask if you want to claim the old backup like it did for this person?
 
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Why would you expect this?
Because I figured it was computer specific. My 2011 iMac was the first and only machine I've ever used Time Machine on. I've never attempted to migrate all my backups to another computer. My expectation - which may even be different to what Apple claim Time Machine can do (do they even cover this aspect?) - is that I would have to start again, but if I didn't have to, that would have been a bonus. That just how I figured it would work.
 
Maybe it's because APFS and Mac OS Extended.
Can be dumb, but if the abovementioned won't help, maybe possible will be to copy a backupdb folder to a new APFS created volume? After that, you can try to add him as the existing backup to see if works
 
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The old MacBook Pro was running MacOS 10.14.6 and new one is running latest 12.2.1
The old TM disk will be formatted as HFS+. Even if you could find a way of adopting that disk, now is the time to start with a fresh backup. Use a new disk and keep the old TM disk in case you need to recover anything.

Why do I say this?

Because TM can now format a new destination disk with APFS format. This brings major advantages in terms of reliability - mostly because the hard directory links used by TM to HFS were 'fragile' and a major cause of corruption. TM to APFS uses the snapshot functionality of APFS to construct each backup as a snapshot - this is much more robust. There are also less obvious advances in terms of performance and disk usage.

So move on and embrace the new TM.
 
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If every single thing from the Time Machine backup is now on your new computer, I would honestly just wipe the drive and start fresh.
 
OP said he's running 10.14, which is Mojave. APFS was brought in with either Sierra or High Sierra I forget which, either way it's highly unlikely his old one wasn't APFS. I'm not sure why a few people here assume it isn't.
 
Starting with Catalina, the Mac's HD is split into two volumes.

Interesting, mine isn't? Since I migrated I only have the 1 Volume which is exactly the same as my old MacBook Pro (called MKBK).

But actually now that I look in Disk Utility I see it has split the drive up into 2 parts (though they aren't really partitions? which is odd). And there is a "Data" section there. I wonder if I can just rename that "MKBK" to match the backup drive? Honestly I really hate this new file structure, really doesn't make sense to me.

So what is in the other section that is locked?

Also just realized that the first MKBK section has a mount point of "/" which is the root directory and what all the material Time Machine material says you need to associate (that's what I've been typing in)... however the accessible section "Data" has a mount point as /System/Volumes/Data so maybe that's the path I need to associate to the old backups?

If you do it through the Time Machine UI, does it ask if you want to claim the old backup like it did for this person?

I actually did try that and nothing happened, I got no message. The only message I ever got from the OS was after I migrated and did my first new backup it asked if I wanted to Inherit the backup drive. So that's why I've been trying to force the association through Terminal commands.
 

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Because I figured it was computer specific.

but if I didn't have to, that would have been a bonus. That just how I figured it would work.

No it's not computer specific. When you buy a new Mac you have the option during installation to migrate from a Time Machine backup (or even an attached Mac through another connection like Firewire / Ethernet) and it mirrors your old computer to your new one 100%. The screen will say "Transfer Information to This Mac" which is basically running Migration Assistant (you can actually run that app anytime).

So when you use your new Mac you can pickup exactly where you left off on your old one. I've done this many times over the years, simply mirroring my old system to my new computer which has been awesome. Time Machine has always picked up from the old one as well basically associating the new computer to the old backups. This is the first time it hasn't done that.


 
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Maybe it's because APFS and Mac OS Extended.

That's what I'm starting to think as well! But it seems odd, Apple supports Time Machine volumes as Mac OS Extended so why would it matter what the format is when doing the backup? It should be just copying the files and forming links to the earlier backups to create a complete set of files.

copy a backupdb folder to a new APFS created volume?

I can't easily do that as I backup to a drive that's basically a centralized NAS (a 20TB Drobo). The backupdb capturing over 6 years of backups would be huge (Probably 10+TB).
 
now is the time to start with a fresh backup.

With the way I work I just find that highly annoying. I like having everything centralized (which is why I use NAS type devices, so I can just up the size of the drives every few years to gain more space). I like being able to "Enter Time Machine" and go to any point in time over the last 6+ years, it's a lot simpler. Moving to a separate drive simply to support APFS is just messy to me.
 
If every single thing from the Time Machine backup is now on your new computer

It's not, I have current files migrated to my new computer, but Time Machine has over 6 years of backups in it, probably over 10TB of backups.
 
That's correct, my Old Mac was Mojave and Time Machine volume is HFS+, Mac OS Extended.
Aha. Likely that's the reason then. The file systems are just fundamentally incompatible.
Probably you will have to do what I expected to do: file my old TM backups under 'just in case' and start afresh.
Realistically how often do you need to browse through 6 years of backups.
 
I agree with everyone else. So much has changed since Mojave. I think it'd be wise to set this one aside and create a new Time Machine backup. It'll use the new APFS file system and be more efficient. If I remember correctly, quite a few people (myself included) had problems after upgrading to Big Sur due to all the changes that were made under the hood. My Time Machine disk is on a NAS and my backups run faster than it used to now that it is using APFS.

I think you're lucky you've made it 6+ years without any issues. I wouldn't put all my eggs in one basket though. If something goes wrong with the Time Machine disk, *POOF!* 6+ years of backups are lost. Following the advice others have given me in the past, I now create a new Time Machine disk after every major OS upgrade, and keep the previous ones for safe keeping.
 
Interesting, mine isn't? Since I migrated I only have the 1 Volume which is exactly the same as my old MacBook Pro (called MKBK).

But actually now that I look in Disk Utility I see it has split the drive up into 2 parts (though they aren't really partitions? which is odd). And there is a "Data" section there. I wonder if I can just rename that "MKBK" to match the backup drive? Honestly I really hate this new file structure, really doesn't make sense to me.

So what is in the other section that is locked?

Also just realized that the first MKBK section has a mount point of "/" which is the root directory and what all the material Time Machine material says you need to associate (that's what I've been typing in)... however the accessible section "Data" has a mount point as /System/Volumes/Data so maybe that's the path I need to associate to the old backups?



I actually did try that and nothing happened, I got no message. The only message I ever got from the OS was after I migrated and did my first new backup it asked if I wanted to Inherit the backup drive. So that's why I've been trying to force the association through Terminal commands.
Things still look the same in Finder, the end user really doesn't notice anything different. You have to go into Disk Utility to see all the different volumes. (A volume is not the same as a partition.) I once read a good blog article explaining all of this when it was new, but can't find it anymore. This is the best one I could find after a quick search.


It may also be worth mentioning so you're aware... Since Time Machine no longer backs up the operating system, you cannot use Time Machine to restore/recover a machine anymore. You'll first have to install the OS manually, and then restore your data.

 
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It's not, I have current files migrated to my new computer, but Time Machine has over 6 years of backups in it, probably over 10TB of backups.
If you have every current file then the answer is yes. You don’t need any of that 10 terabytes of stuff. Time Machine keep making back ups until you run out of drive space and then purge the old stuff 6 years from now it will be like you deleted your entire drive because none of the sane back up files will be on there. If you have the most recent time machine backup restored on your computer then you should erase the drive and start fresh. The only reason you should keep that is if you think there is some old file on there you don’t have, but looking for that is going to be a huge pain in the butt.

Or if you truly hate this idea, get another external drive and store your current drive somewhere else.
 
If you have every current file then the answer is yes. You don’t need any of that 10 terabytes of stuff. Time Machine keep making back ups until you run out of drive space and then purge the old stuff 6 years from now it will be like you deleted your entire drive because none of the sane back up files will be on there. If you have the most recent time machine backup restored on your computer then you should erase the drive and start fresh. The only reason you should keep that is if you think there is some old file on there you don’t have, but looking for that is going to be a huge pain in the butt.

Or if you truly hate this idea, get another external drive and store your current drive somewhere else.
The OP is using a NAS for their Time Machine, so it's even simpler than wiping a physical disk or getting a new one. (When backing up to a NAS, it uses a virtual Time Machine disk.) All they need to do is create a new share to hold the new virtual disk, and leave the other one alone. They'll still have the old stuff in the old Time Machine share/disk and can access it if they really need to.

I can appreciate wanting to keep the entire history in a single Time Machine backup, but it just isn't a good idea...especially if it's the only backup strategy.
 
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