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Back up Time machine

Why it takes so long to backup. It can go for hours the "Preparing back up". I understand it takes a long time. But how many hours? When can I know something is wrong?


Thanks,

MacBook Pro 13″, macOS 10.15

Posted on May 30, 2021 8:12 AM

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Question marked as Top-ranking reply

Posted on May 30, 2021 12:02 PM

beatriz27 wrote:

I have purchased 3 different hard dirves. Never been able to complete a back up.

it has never given me a message. I look it up at the Time Machine Icon. Now, I choose to Back up. I should be creating a new one, but again is showing. "Preparing Back up".

i have my Mac Book Pro since 2012. Never been able to have a Time Machine BAck Up. Today I decided to ask about it. I do my own back up. Just sending file to an external Disk. I have 2 of those... But, I was wondering why can´t I have a normal time Machine Back up, as everybody.
Beatriz

Let it run overnight, if you have never completed one then it is doing the first one and those can take a very long time, especially on an older Mac.


Some things that can affect backups (and make them take a long time):


  • If your Macbook Pro has a mechanical internal drive (does it?)
  • It can take several hours or more to scan both the internal drive and external drive to do the first backup
  • Size of the internal drive being backed up (how large is yours)
  • The type of backup drive (is it USB 3? Or USB 2 which is much slower?)
  • If you have installed any anti-virus apps or "cleaner" or "optimize" software, these can make things very slow. I have found backups on my work computer, which has to have anti-virus, can take hours while on my home machines they take seconds to at most a few minutes.
  • You can download and run the diagnostic software Etrecheck, give it full disk access permissions, and post the output here. If something that is installed is causing your problem, people here will likely find it from the output.
10 replies
Question marked as Top-ranking reply

May 30, 2021 12:02 PM in response to beatriz27

beatriz27 wrote:

I have purchased 3 different hard dirves. Never been able to complete a back up.

it has never given me a message. I look it up at the Time Machine Icon. Now, I choose to Back up. I should be creating a new one, but again is showing. "Preparing Back up".

i have my Mac Book Pro since 2012. Never been able to have a Time Machine BAck Up. Today I decided to ask about it. I do my own back up. Just sending file to an external Disk. I have 2 of those... But, I was wondering why can´t I have a normal time Machine Back up, as everybody.
Beatriz

Let it run overnight, if you have never completed one then it is doing the first one and those can take a very long time, especially on an older Mac.


Some things that can affect backups (and make them take a long time):


  • If your Macbook Pro has a mechanical internal drive (does it?)
  • It can take several hours or more to scan both the internal drive and external drive to do the first backup
  • Size of the internal drive being backed up (how large is yours)
  • The type of backup drive (is it USB 3? Or USB 2 which is much slower?)
  • If you have installed any anti-virus apps or "cleaner" or "optimize" software, these can make things very slow. I have found backups on my work computer, which has to have anti-virus, can take hours while on my home machines they take seconds to at most a few minutes.
  • You can download and run the diagnostic software Etrecheck, give it full disk access permissions, and post the output here. If something that is installed is causing your problem, people here will likely find it from the output.

May 30, 2021 9:03 AM in response to beatriz27



beatriz27 wrote:

Why it takes so long to backup. It can go for hours the "Preparing back up". I understand it takes a long time. But how many hours? When can I know something is wrong?

Thanks,

?


Brand new backup, old backup...



"Time Machine has completed a new backup for you, or get a message saying it can't create the backup,"

or “failed to complete the backup, ” or “Preparing backup”


This message reappears most likely the TimeMachine disk is operating in a state of failure and will continue to fail with increasing frequency, in this case replace the drive.





If you need to create a new backup from Mac—

https://support.apple.com/guide/mac-help/if-you-need-to-create-a-new-backup-mh34042/11.0/mac/11.0




May 30, 2021 12:21 PM in response to steve626

Let it run overnight, if you have never completed one then it is doing the first one and those can take a very long time, especially on an older Mac.

-- When I do this.. Once it has no action it goes to sleep. And back up stops.


  • If your Macbook Pro has a mechanical internal drive (does it?)

-- The only upgrade has been in RAM.


  • It can take several hours or more to scan both the internal drive and external drive to do the first backup

-- Understood


  • Size of the internal drive being backed up (how large is yours)

500K


  • The type of backup drive (is it USB 3? Or USB 2 which is much slower?)

-- 2T Seagate, can´t find USB number. I suppose it is USB 3


  • If you have installed any anti-virus apps or "cleaner" or "optimize" software, these can make things very slow. I have found backups on my work computer, which has to have anti-virus, can take hours while on my home machines they take seconds to at most a few minutes.

-- I have in the past. But erased them all.


  • You can download and run the diagnostic software Etrecheck, give it full disk access permissions, and post the output here. If something that is installed is causing your problem, people here will likely find it from the output.

-- I will send it in next post.


It does show I need to change Drive, Which I am looking forward to do it. I need my full back up.


Thanks!!

May 30, 2021 11:28 AM in response to leroydouglas

I have purchased 3 different hard dirves. Never been able to complete a back up.


it has never given me a message. I look it up at the Time Machine Icon. Now, I choose to Back up. I should be creating a new one, but again is showing. "Preparing Back up".


i have my Mac Book Pro since 2012. Never been able to have a Time Machine BAck Up. Today I decided to ask about it. I do my own back up. Just sending file to an external Disk. I have 2 of those... But, I was wondering why can´t I have a normal time Machine Back up, as everybody.

Beatriz

May 30, 2021 1:13 PM in response to beatriz27

My experience with excessively long preparing, is that Time Machine is running a File System CHeck until the covers.


It would be doing this because it felt the file system on the backup disk was broken.


Broken, could be from not properly unmounting the external disk before disconnecting the disk’s cable or powering down the disk. For example, closing the lid to a Macbook, uncabling it and walking away.


Look at Applications -> Utilities -> Activity Monitor -> View (menu) -> All Processes -> CPU (tab), and using the upper left Search box, search for:


fsck


if you find an fsck process, then you will know that Time Machine is attempting to repair a broken file system. On terabyte sized disks with a lot of data already on them, it can take a very long time for fsck to run.

May 30, 2021 1:42 PM in response to beatriz27

If your internal drive is failing, that could also interfere with a successful Time Machine backup being done for the first time.


I suggest that you download SuperDuper or Carbon Copy Cloner. I believe that each provides a free version, at least for a limited initial period of us. I think SuperDuper is free for a version without additional features.


Try to make a backup/clone of your internal drive with one of these tools. Based on what Bob Harris and leroydouglas said, you should first run Disk Utility to check the condition of both your internal drive and the condition of the destination drive for the backup. It might be best to try to create TWO backups (the second being on a second drive) given the questionable health of one or more drives that you have.


When you replace your internal drive, you can migrate your files back from one of these clone backups. Keep the other around just in case something goes awry. Apple's Migration Assistant will work with these types of backups as well as with Time Machine backups.

May 31, 2021 7:59 PM in response to beatriz27

There are several issues, such as repeated crashes (hundreds are listed) and a number of system extensions (kexts), which can be notorious for interfering with the operating system if they are old or outdated.


But the main issue is the "poor" performance which appears to be caused by a "failing" drive that is a mechanical drive which, since you are on Catalina, is set up as an APFS drive. APFS on mechanical drives is very inefficient and slow. But you also have a failing drive. To give you a sense of the magnitude of the issue, the disk is probably thrashing with many errors, and hence operating very slowly with crashes when it cannot recover from an error. Etrecheck took 38 minutes to run; running it on my laptop took about 1 minute. So that's a factor of 40x; the first Time Machine backup can easily take an hour in the "preparing..." phase as it assess all the directories and files and prepares that first backup (after the first backup, subsequent backups often take seconds to minutes), but yours might requires 40 hours or more with that factor of 20x, hence it appears to never actually finish preparing for that first backup.


As you indicated in your post, job #1 is to make a backup (clone) and then replace the internal drive. Test the backup with some random files and check the space taken by the backup to make sure it looks like a good backup. For your new drive, I suggest an SSD, no more mechanical drives. No way to tell if the crashes and poor performance are solely due to the failing hard drive. This might be an opportunity, however, to migrate only user files/accounts to your new drive from your backup, and then install only things you really need, from scratch, with the latest versions and latest installers.


If you are not familiar with replacing an internal laptop drive, an Apple Authorized Service Provider can handle that for you. I recently replaced an internal SSD in a 2013 laptop and purchased the drive myself, the service provider charged $35 to replace it. They can also help you with the migration back from your backup (another $35), but I always do that myself, it is very straightforward.

Back up Time machine

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