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HD shows 400gb free-Backup drive shows 50GB-won't back up

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bladerunner616

macrumors member
Original poster
May 17, 2014
72
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On my 2023 Mini I have a 1TB drive with 410GB free. My Seagate 1TB backup drive only shows 50GB free and won't backup due to lack of space.

I ran the Disk Utility First Aid on the Seagate and still have the lack of storage space.

Any suggestions, please?

Thanks.
 
You need a bigger backup disk.

Backups don't store just what's on your computer now, they store versions of files going back in time. Time Machine's backup rules include storing hourly backups for 24 hours and daily backups for a month. Weekly backups are then stored as long as possible, but weeklies will be purged if needed to free space. So right now, your hourly and daily backups (non-purgeable) are too large to allow a new backup to run.

Two things to keep in mind with Time Machine:
1. Ensure you have enough space for all the versions of all the files you want backed up
2. Exclude folders that have rapidly-changing, large files that are transient in nature & don't need to be backed up (e.g. "Scratch" folders; temporary import folders for photos/videos, etc)

As a general rule for my data, I want my backup to be 2x-3x my total data storage. I have about 2.5TB stored, and I'm using an 8TB disk to back it up. The vast majority of my data is fairly static (photos & media); if your data is more dynamic such as editing videos a lot then you might need a higher ratio.

If you do have large, temporary files included in your backup that don't need to be - you could erase the backup disk, set your exclusions appropriately, and re-start backups. A better idea is add a NEW backup disk of appropriate size, start NEW backups on that, and then once up to date erase your old 1TB disk and use it for data or whatever.
 
I really don't need daily and weekly backups. If I set it to manual backups, can I get around my storage space issues?

Or can I just reformat the external drive now and then?

Thanks.
 
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Reformatting should work every time. But of course you are wiping out your backup history at that time. In a Murphy's law loss of the Mac right at that time, you'd be data "naked" with nothing to recover at all.

FrekinEurekan is right: buy yourself a larger-to-much-larger backup drive and use it for TM backups. General rule of thumb is take total storage of all Macs to be backed up and multiply by 3 or 4- the bigger, the better.

Then let TM work like it is supposed to work. TM is not just a one-off backup system. The other benefit is in the name: the ability to step backwards in time to recover up to many copies of some file. If you have plenty of space, some important file might have 20 or 30 backups in TM. Suppose #13 is a corrupted version of an important file. If so, #14-20 or 30 will be corrupted too. You won't necessarily know until you try to touch the file again. With multiple backup copies, you can step back to the last good version (#12 in this example) and recover.

People usually overlook this big benefit, thinking they want just one good backup... but never knowing for sure they have one good backup of all files until they are trying to recover. That's the wrong time to discover your one backup copy is corrupt.

WHILE YOU ARE AT IT: the better, fuller recommendation is to juggle at least TWO such big drives for TM, with one recent backup stored offsite. This protects against fire-flood-theft scenarios that easily take out main computer and DAS at home. Regularly rotate TM onsite with TM offsite to keep the offsite backup up to date. I do exactly this with the onsite one as my regular TM drive for a month, then swap it with the offsite to take over for the next month. My very worst case exposure would be fire-flood-theft on about day 29, just before the rotation. I store my offsite drive in a bank safe deposit box.

In just a quick check, I'm seeing 8TB 3.5" HDDs for about $100 online right now. Or if you are wiling to consider refurbished drives, the same will buy about 14TB of storage. So that's two for onsite-offsite rotation for about $200... a small price to pay for more confidence in all potential data loss scenarios.
 
HobeSoundDarryl said:
Reformatting should work every time. But of course you are wiping out your backup history at that time. In a Murphy's law loss of the Mac right at that time, you'd be data "naked" with nothing to recover at all.

FrekinEurekan is right: buy yourself a larger-to-much-larger backup drive and use it for TM backups. General rule of thumb is take total storage of all Macs to be backed up and multiply by 3 or 4- the bigger, the better.

Then let TM work like it is supposed to work. TM is not just a one-off backup system. The other benefit is in the name: the ability to step backwards in time to recover up to many copies of some file. If you have plenty of space, some important file might have 20 or 30 backups in TM. Suppose #13 is a corrupted version of an important file. If so, #14-20 or 30 will be corrupted too. You won't necessarily know until you try to touch the file again. With multiple backup copies, you can step back to the last good version (#12 in this example) and recover.

People usually overlook this big benefit, thinking they want just one good backup... but never knowing for sure they have one good backup of all files until they are trying to recover. That's the wrong time to discover your one backup copy is corrupt.

WHILE YOU ARE AT IT: the better, fuller recommendation is to juggle at least TWO such big drives for TM, with one recent backup stored offsite. This protects against fire-flood-theft scenarios that easily take out main computer and DAS at home. Regularly rotate TM onsite with TM offsite to keep the offsite backup up to date. I do exactly this with the onsite one as my regular TM drive for a month, then swap it with the offsite to take over for the next month. My very worst case exposure would be fire-flood-theft on about day 29, just before the rotation. I store my offsite drive in a bank safe deposit box.

In just a quick check, I'm seeing 8TB 3.5" HDDs for about $100 online right now. Or if you are wiling to consider refurbished drives, the same will buy about 14TB of storage. So that's two for onsite-offsite rotation for about $200... a small price to pay for more confidence in all potential data loss scenarios.
Click to expand...
I understand your concern about fire and Murphy's law. I have to consider the risk. Where are you finding refurbished 8TB drives for $100 a pair. As I have a 1TB system, I really don't need 8TB. Thanks.

It did just occur me that two 1TB external drives would do the trick. Just reformat one and have the other current. And swap them back and forth off site as needed.

That should be a pretty cheap fix.
 
bladerunner616 said:
I understand your concern about fire and Murphy's law. I have to consider the risk. Where are you finding refurbished 8TB drives for $100 a pair. As I have a 1TB system, I really don't need 8TB. Thanks.

It did just occur me that two 1TB external drives would do the trick. Just reformat one and have the other current. And swap them back and forth off site as needed.

That should be a pretty cheap fix.
Click to expand...

Not $100 pair, $100 each... so $200 for 2 drives with plenty of storage for the "time" part of Time Machine. Hop on Amazon and type 8TB HDD in the search box. And Amazon is not necessarily lowest price- just what I checked for quick pricing.

If you have a 1TB Mac, you should be aiming for at least a 3TB-4TB TM drive, if not larger. The general guiding "rule" is multiply total capacity times 3 or 4 as a minimum.

And if you have more than 1 Mac to keep backed up, add total capacity of both and then multiple by 3 or 4 if not more. For example, main Mac has 1TB and spare has 500GB, 1.5 times at least 3 is pointing you towards at least about 5TB for TM to back up both Macs.

I know you can make it work with 1TB but you are trading off your "Time Machine" history. It's called that instead of "Apple Backup" or "Apple Cloner" because maintaining history is a valuable benefit in recovery.

If you want only a single backup of existing drives- a "clone" if you will- you might want to switch to using Carbon Copy Cloner or Super Duper instead. Both are free and work well. If I wanted to keep my backup drive small, I'd use them instead of TM.
 
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HobeSoundDarryl said:
Not $100 pair, $100 each... so $200 for 2 drives with plenty of storage for the "time" part of Time Machine. Hop on Amazon and type 8TB HDD in the search box. And Amazon is not necessarily lowest price- just what I checked for quick pricing.

If you have a 1TB Mac, you should be aiming for at least a 3TB-4TB TM drive, if not larger. The general guiding "rule" is multiply total capacity times 3 or 4 as a minimum.

And if you have more than 1 Mac to keep backed up, add total capacity of both and then multiple by 3 or 4 if not more. For example, main Mac has 1TB and spare has 500GB, 1.5 times at least 3 is pointing you towards at least about 5TB for TM to back up both Macs.

I know you can make it work with 1TB but you are trading off your "Time Machine" history. It's called that instead of "Apple Backup" or "Apple Cloner" because maintaining history is a valuable benefit in recovery.

If you want only a single backup of existing drives- a "clone" if you will- you might want to switch to using Carbon Copy Cloner or Super Duper instead. Both are free and work well. If I wanted to keep my backup drive small, I'd use them instead of TM.
Click to expand...
But I could certainly back up to one drive using a freshly wiped drive while the other is intact. And just swap them out. And keep one off site. You certainly made a valid point to keep one off site.

That should work.

I only have one computer, so that does make things easier for me.
 
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You're using time machine, right?
A tm backup will grow, and GROW, and GROW, because it keeps backing up the same stuff over and over and over and over and over again.

If you want a backup that doesn't grow, and reflects your internal drive as it currently "is" (at the last backup), then use either CarbonCopyCloner or SuperDuper.

A cloned backup created by either of the above will remain pretty "stable" in size over time.
 
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Fishrrman said:
A cloned backup created by either of the above will remain pretty "stable" in size over time.
Click to expand...
Should be completely stable - as it doesn't include any history, just what's "there right now." Including any deleted/corrupted files.

IMO a "Backup" is distinct from a "Clone." Clones have their place, but they don't protect against accidental overwrite/deletion/corruptions like a true backup scheme will.
 
The grow, grow, grow concept is key to TM. It's like having an actual Time Machine but you can only hop back 1 hour ago. That's nice. Or would you prefer a model that can hop back weeks or months ago? Better.

The classic example: you want to finally write a book. You are far along out at chapter 18 and nearing the end. TM has been backing it up all along. Suppose you accidentally delete chapters 2 & 3 at some point and don't catch your mistake at the time. The file will still save and you can continue on to the end of the book. Maybe that takes another 3 weeks? Finally, book is done and it's time for a final proofreading pass. Then you realize that somewhere along the way, you deleted chapters 2 & 3. :eek:

If you've got only a clone, those chapters were also deleted on it as soon as you cloned it after the accident. They are completely lost. To recover them means having to re-write them again.

However, if you have a TM backup, you can start working your way through the versions saved all along the way, until you find the latest backup that includes those 2 chapters. You can then copy them out of that version and into the final version. Your book is whole again. You don't have to try to recall what chapter 2 & 3 were about and rewrite them.

The same applies to anything created over a span of time. Keynote presentations? Music composition? Videos? Any kind of written document (book, plans, forecasts, analysis, etc). Photo collections. Music collections. Art. Etc. At any point during the creative process you can accidentally delete earlier, perfected work... and not necessarily notice until later. With TM backups, the lost can be found again. With the clone approach, it's probably completely lost unless you catch the mistake BEFORE you replace the clone copy.

The clone that backs up only current files will back up corrupted files just as readily it does good ones. Ever saved a file and all seems fine until next time you try to open it and can't (because it got corrupted somehow)? That's the whole file now lost. Clone it before you discover this and the clone will be the same un-openable file. With TM, you can step backwards to prior versions of the file that will open, recover the latest that will open and thus save the day.

That's the big difference between the two... and why it is called Time Machine instead of something like Apple Cloner or similar. CCC and SuperDuper have their place but TM approaches it in a different way. All one has to do is buy enough storage to buy plenty of opportunity to step far enough into the past to recover anything. Gigantic storage is dirt cheap (upwards of 16-24TB or more costs only a fraction of one iPhone price, in a device you'll probably be able to use while upgrading to 3 or more iPhones over time). I consider it well worth it.
 
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Any functional, reliable drive can be fine. Is the max capacity of that one = to at least 3 times the total capacity of all Macs you want to back up?

If you also have some external storage hooked to that Mac, add its total capacity to the number and then multiply by at least 3. For example, if you have- say- 1TB inside your Mac and maybe 3TB as an external drive with files important to preserve in fire-flood-theft scenario, you need a TM disc that is at least 4TB X 3 or 12TB to back both up with a pretty good history for "back in time" recovery.

Or consider the 1TB in your mini + the 1TB in the existing Seagate (which could now be more general purpose storage for your Mini) = 2TB times (at least) 3 = 6TB or more. With that in mind, I'd consider 4TB too little (even if a lot of the space on the internal and the Seagate would be empty. It's easy to grow into filling 2TB over the life of a TM backup drive. So assume near "full" and thus, needing 3X or more of full drives.

The 3X multiple is considered the general guideline minimum for a TM drive. The more storage you have, the further back in time you can go when you need to recover. It appears that one at 4TB is $35. I see 10TB externals on Amazon for about $100. A good HDD can last 10+ years (I have some that still work after 20 years). Unless money is really tight, go big! The more history you can store, the further "back in time" you can go.
 
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OP asked:
"What do you think of using something like this, please? Thanks.
It is cheap but I thought I would ask."

Something about that offer just doesn't look right to me.
I'd look elsewhere.

If you're going to use tm (again, I don't and never will), I'd suggest a 2.5" SATA 4tb platter-based hard drive in a USB3 enclosure.

If I was buying a platter-based drive, I'd look for a Toshiba or HGST (Hitachi).
Here's some:

Amazon.com: Toshiba 2.5" Hdd 4tb

Amazon.com: toshiba 2.5" hdd 4tb
www.amazon.com

For an enclosure, something like this will do:
(apologies for the long link)
 
As an Amazon Associate, MacRumors earns a commission from qualifying purchases made through links in this post.
I got my new (refurbed) 4TB WD drive in. I thought it would be a good idea to restore my Mac from a Time Machine backup and then start using the new drive. But I did something really wrong and it restored something I really don't recognize.

Files and apps are missing, old apps are present, it is really confusing.

I am wondering if I should just wipe the new computer and do a backup directly from the old one. My wireless keyboard does not let me do the command+r when restarting so I could also just get a wired keyboard and try some of the other things listed on the TM options.

I tried to do some different restorations from TM but it says I don't have enough space.

Any thoughts on this, please?

Thanks.
 
Restoring from a TM disc doesn't require more space... only enough space on the internal drive to restore.

I don't understand why you thought that was a "good idea" in the first paragraph if the Mac to which you restored was the same Mac from which you were backing up to the original TM drive. Conceptually, the Mac already had all the files on it that it should and that's what you were then backing up to the original TM drive. A restore from the TM drive wouldn't do anything since- in a restore process- it is only looking to put files back that are not there. All files you wanted to back up should have been there, so no restore should be necessary. I would guess that a TM restore would end up doing nothing in such a scenario, since it wouldn't find files missing to restore.

The right thing to have done was to simply plug in the new 4TB, select it as your new TM drive and let it back up that same Mac. It would essentially be taking over as your TM backup disc.

Your description is confusing. One way I read it is like you've got a new Mac (perhaps different than the Mac mini you referenced in post #1). Post #1 reads like you have a 2023 Mac mini backed up to a TM disc and the TM disc is showing that it is full. Post #15 seems to imply there is a "new computer" with consideration to "do a backup directly from the old [computer?]."

If there is a new computer, instead of a restore from another computer's TM backup, you should be using a different program called "migration assistant" (in the utilities folder) to then import from the TM backup to the new computer, not TM. If you have restored one Mac to another instead of using migration assistant, that fits your description of "looks different", "apps & files are missing", etc... and possibly explains a "not enough room" message too. And if this, the remedy is likely:
  • Reset the new Mac to new again (basically wiping anything restored to it)
  • Boot into it like a brand new Mac owner would.
  • There will be a screen in the setup process that will ask if you want to migrate from another computer or a Time Machine backup. You can choose either and follow the instructions. That will NOT be restoring a TM backup from another computer but running "Migration Assistant". What you want to happen is the same but how it does it is different.
  • That process may take a while so just let it do its thing.
  • When it is done and you finish the steps associated with firing up a new Mac, it may still look different if the new Mac is running a newer macOS than the old Mac. But your files & apps should generally be where you expect them to be.
If there is no new computer and all this is about the 2023 Mini, while you should NOT have restored to it if it was as you wanted it before the restore (no benefit to that at all), if you have and now it looks different, you'll need to share more information. Assuming the TM backup was from this same computer, a restore to this computer should not alter apps & files. In short: it should look "the same" as it did when you did the last backup to that drive. It may require another restore but the outcome you describe doesn't fit the logic of how TM "restore" works.

If there are 2 Macs involved plus one TM backup drive, I suggest throwing all of that in the car and heading for an Apple Store for in-store help. You may be getting into complications that are going beyond what strangers are able to help you do relative to your own knowledge & experience with all of this. In store, they can reset the new Mac "to factory" and then help you run the initial boot and "migrate" your information from either the Mac Mini or the TM backup.
 
HobeSoundDarryl said:
Restoring from a TM disc doesn't require more space... only enough space on the internal drive to restore.

I don't understand why you thought that was a "good idea" in the first paragraph if the Mac to which you restored was the same Mac from which you were backing up to the original TM drive. Conceptually, the Mac already had all the files on it that it should and that's what you were then backing up to the original TM drive. A restore from the TM drive wouldn't do anything since- in a restore process- it is only looking to put files back that are not there. All files you wanted to back up should have been there, so no restore should be necessary. I would guess that a TM restore would end up doing nothing in such a scenario, since it wouldn't find files missing to restore.

The right thing to have done was to simply plug in the new 4TB, select it as your new TM drive and let it back up that same Mac. It would essentially be taking over as your TM backup disc.

Your description is confusing. One way I read it is like you've got a new Mac (perhaps different than the Mac mini you referenced in post #1). Post #1 reads like you have a 2023 Mac mini backed up to a TM disc and the TM disc is showing that it is full. Post #15 seems to imply there is a "new computer" with consideration to "do a backup directly from the old [computer?]."

If there is a new computer, instead of a restore from another computer's TM backup, you should be using a different program called "migration assistant" (in the utilities folder) to then import from the TM backup to the new computer, not TM. If you have restored one Mac to another instead of using migration assistant, that fits your description of "looks different", "apps & files are missing", etc... and possibly explains a "not enough room" message too. And if this, the remedy is likely:
  • Reset the new Mac to new again (basically wiping anything restored to it)
  • Boot into it like a brand new Mac owner would.
  • There will be a screen in the setup process that will ask if you want to migrate from another computer or a Time Machine backup. You can choose either and follow the instructions. That will NOT be restoring a TM backup from another computer but running "Migration Assistant". What you want to happen is the same but how it does it is different.
  • That process may take a while so just let it do its thing.
  • When it is done and you finish the steps associated with firing up a new Mac, it may still look different if the new Mac is running a newer macOS than the old Mac. But your files & apps should generally be where you expect them to be.
If there is no new computer and all this is about the 2023 Mini, while you should NOT have restored to it if it was as you wanted it before the restore (no benefit to that at all), if you have and now it looks different, you'll need to share more information. Assuming the TM backup was from this same computer, a restore to this computer should not alter apps & files. In short: it should look "the same" as it did when you did the last backup to that drive. It may require another restore but the outcome you describe doesn't fit the logic of how TM "restore" works.

If there are 2 Macs involved plus one TM backup drive, I suggest throwing all of that in the car and heading for an Apple Store for in-store help. You may be getting into complications that are going beyond what strangers are able to help you do relative to your own knowledge & experience with all of this. In store, they can reset the new Mac "to factory" and then help you run the initial boot and "migrate" your information from either the Mac Mini or the TM backup.
Click to expand...
Four points:
I realize now just now not plugging in the new drive straight away was a bad idea.

I have been using Migration Assistant

I already thought of your suggestion reseting the Mac.

The Apple store remains an option


Thank you.
 
My fix for my blunder was pretty simple. I just backed up my old computer to the new 4TB drive and erased the new computer before doing the transfer.

Worked great.
 
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