TIME MACHINE doesn't allow me to back up unless I erase previous files

[whatisreal]

Hi there. I'm trying to backup my macbook pro 2015 but TIME MACHINE is rejecting the operation. I'm using an external Western Digital of 5TB and TIME MACHINE says that I have to erase what's inside already otherwise it won't backup. Is there a solution?
Thank you.

 

[IWT]

Firstly, a warm welcome to Mac-Forums.

Time Machine requires an "empty" External Hard Drive (EHD) which is formatted appropriately.

This is logical because Time Machine requires a specific format and in doing this there should not be any other data on it.

So, from your viewpoint, you need either a new EHD or one which you already have, in which case you have to erase all data already on it (if there was any on it already) and then allow Apple to format the drive.

This is where we need to know which Operating System (OS) you have because the formatting is, to an extent, dependent on the OS.

Assuming that you have Monterey or Ventura, the format is APFS (Case sensitive) and your Mac will do this for you.

Perhaps you could help us by giving us your Mac, model, year and Operating System.

It's really very easy to do

Ian

 

[pm-r]

Firstly, a warm welcome to Mac-Forums.

Well Ian, I suspect that your reply post should help fix whatisreal's problem, but it looks like they have actually been a member for quite some time now and actually Joined May 2, 2019.

But it appears they just haven't done much in the way of posting to the forums here.




- Patrick
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[IWT]

Patrick,

You are correct, but it is the first post from the OP and, well, I thought I'd just welcome @whatisreal anyway.

Ian

 

[Rod]

whatisreal, I assume you have a lot of data on your 5TB EHD already.
As mentioned, we don't know much about your computer but as it's a 2015 MBP I'll assume it's storage is only 500GB.

For Time Machine you really only need an EHD of about twice the size of your internal drive and it's best to use a dedicated drive because of it's formatting, as mentioned, so 1TB for 500GB would be plenty.

Ideally this should be an SSD (flash drive) but it doesn't have to be. I have been using a 1TB Transcend HDD (spinner drive) for TM on my 500GB M1 MBP for some years with no problems other than it's a bit slow.
So my advice to you would be to buy a dedicated 1TB HDD (or SSD if you can afford it) for your TM backup and keep the 5TB drive for whatever purpose you currently use it.

The only other option you have would be to shift all the data off your 5TB drive, erase it and partition it so that TM had a dedicated partition to use for TM but apart from the obvious difficulty of doing that it's not advised to "put all your eggs in one basked" so to speak because it risks loosing everything if something goes wrong like eg. forgetting to eject both partitions before disconnecting the EHD.

 

[whatisreal]

It's a macbook pro early 2015 with Monterey.
So I had to format the drive before storing files. Is there another software that would make backups like Time Machine but without the need to format?
Thank you

 

[IWT]

Is there another software that would make backups like Time Machine but without the need to format?

No. I really don't think so.

The beauty of Time Machine is that the first backup (BU) contains almost everything bar the Operating System (OS). Thereafter, the BUs are incremental, meaning that they only include the changes that have occurred since the first BU.

Hourly for 24 hours, thereafter daily for the a month and then weekly ad infinitum. Macintosh allows up to two External Hard Drives (EHD) if you so wish, alternating on the same basis as I described.

Any External Hard Drive that you wish to use for any form of BU, manual or using an app such as TM, requires formatting.

Formatting is the means by which the computer can "speak" to the EHD. This cannot be avoided.

If my post leaves you in any doubt, please say so. No problem there.

Ian

 

[pm-r]

Any External Hard Drive that you wish to use for any form of BU, manual or using an app such as TM, requires formatting.

Formatting is the means by which the computer can "speak" to the EHD. This cannot be avoided.

According to Apple:

Time Machine can’t back up to iPhone, iPad, or iPod or to a disk formatted for Windows. If you connect a disk formatted for Windows, it can be reformatted (permanently removing all data) to a Mac format and used as a backup disk.

APFS or APFS Encrypted disks are the preferred format for a Time Machine backup disk. If you select a new backup disk that’s not already formatted as an APFS disk, you get the option to erase and reformat it. If the disk is a Mac OS Extended format disk that contains an existing Time Machine backup, you aren’t asked to erase and reformat the disk.

Note: The entire APFS volume is reserved for Time Machine backups. If you want to store files other than the Time Machine backup on the same physical device, use Disk Utility to create an additional APFS volume on the disk. The two volumes then share the available space.

Types of disks you can use with Time Machine on Mac

Use Time Machine on your Mac with a Time Capsule and with USB and Thunderbolt disks.

support.apple.com

- Patrick
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[Rod]

There is nothing on the market quite like Time Machine. It's features are unique. For restoring either your whole computer to a new device or simply restoring a single file to an earlier version it is invaluable. For the relatively small price of a second EHD that can be used exclusively for Time Machine you can have the peace of mind to know that when your internal HD dies, and it will, you can restore all of your settings, documents, photos, music, contacts, applications even your desktop wallpaper and layout exactly as it was and all for free.
Everything else in the way of alternatives, including clones, will still require you to erase the destination drive prior to the first backup.

 

[pm-r]

Everything else in the way of alternatives, including clones, will still require you to erase the destination drive prior to the first backup.

Well, depending on the existing format of the target drive, Carbon Copy Cloner doesn't always require the drive to be erased, but if I recall correctly, it is provided as an option.



- Patrick
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[whatisreal]

Does it mean that TIME MACHINE requires an hard drive only for that purpose? And so no other additional data? Or I just need to format it and it will be ready for both?
I had another external hard drive in the past and I used it both for data and TM without having a separate partition.

 

[MacInWin]

Yes, yes, no.
TM has changed. It now insists on being alone on the Volume. I think you can create a new Volume in the Container that holds the TM backup and use that for data, but not the same Volume.

 

[IWT]

Does it mean that TIME MACHINE requires an hard drive only for that purpose? And so no other additional data?

Correct. As Jake said, and indeed Apple, Time Machine should have its own External Hard Drive (EHD). Yes; there are ways of creating a new Volume for Time Machine on an EHD used for other purposes; but that is asking for trouble.

Ian

 

[toMACsh]

I set up an external drive several years ago with more than one volume, one of which was dedicated to TM backups. Whatever changes Apple has made, they haven’t caused any problems for this setup yet.

 

[MacInWin]

I set up an external drive several years ago with more than one volume, one of which was dedicated to TM backups. Whatever changes Apple has made, they haven’t caused any problems for this setup yet.

Yep, as long as the Volume for TM is only for TM, it won't complain or make any fuss about it.

 

[pm-r]

Correct. As Jake said, and indeed Apple, Time Machine should have its own External Hard Drive (EHD).

In reality and reliability, does this mean should or must have its own external hard drive and does its own partition on the external drive qualify for Time Machine use?

Just curious. And does it matter what Mac OS version is being used?

Maybe some other members would like to know as well.



- Patrick
=======

 

[MacInWin]

In reality and reliability, does this mean should or must have its own external hard drive and does its own partition on the external drive qualify for Time Machine use?

Just curious. And does it matter what Mac OS version is being used?

Maybe some other members would like to know as well.



- Patrick
=======

Patrick, it's been changed in Sonoma, and in Ventura as well. I don't remember when it changed, so it may have been earlier than that. Possibly as long ago as Big Sur, as that is the first iteration of MacOS to require TM to use APFS.

TM now insists on "ownership" of the storage space it has been allocated, changes the format from APFS to APFS (Case-sensitive, Encrypted) and makes it read-only to all activites but itself. That "storage space" might be an entire hard drive, or a Volume on an APFS formatted drive. It could be a partition on a large hard drive if the user partitions the drive in the format process using Disk Utility. But the bottom line is, whatever has been designated for TM is taken over by TM. So if a user designates a 4TB EHD of either rotating or SSD variety, that entire 4TB storage space is now the sole possession of TM. But, if the user formats for APFS and creates more than one Volume in the Container, one of those Volumes can be for TM and the other for general use. But, again, TM will take over that one Volume completely. As I said, I do think that if the TM storage is large the user can create a second Volume on the TM drive in the same Container to store other non-TM data, but I've not tried that myself. Since the change to TM and with the decrease in price for smaller SSDs, I've taken to using a 1TB SSD as my TM drive for the 500GB of data I have on my internal storage.

 

[whatisreal]

Can I create this Volume for TM on the empty space currently available in the EHD? Or the only way is to format the whole hard drive and start all over. And if so, how do I create the two separate volumes?
Also, is there a way to encrypt the hard drive?

 

[MacInWin]

Can I create this Volume for TM on the empty space currently available in the EHD? Or the only way is to format the whole hard drive and start all over. And if so, how do I create the two separate volumes?
Also, is there a way to encrypt the hard drive?

Last question first. You can chose to encrypt a Volume when you create it in Disk Utility. Just select it as the option.

Now, for the earlier question(s). Assuming you mean the 5T drive you mentioned in the first post, what you can do depends on how the drive is formatted. Is it APFS, or not? What does Disk Utility show (a screenshot would be best, if you can make and post it)? If the drive is APFS, there is a way to create a new Volume and let TM use it. If it's in HFS+ (Mac OS extended, or Extended (Journaled)) then it would have to be reformatted/repartitioned (erasing everything now on it). If you have the funds, you might be better off getting a new drive just for TM. Small SSD are not very expensive these days. You only need one about double the size of the data TM will be writing to it, which is generally whatever is ON the source drive.