Time Machine Q

[TaraW]

I am reading the same description of how Time Machine works but it's not really answering my question.

Right now I have 300GB of data on my MacBook Pro and want to get it backed up on my external HD and much of it deleted from my computer. My exHD is 1TB.

From what I'm understanding TM's making multiple backups, which means I'm going to run out of space pretty fast. That doesn't make sense to me so I'm assuming I'm misunderstanding and it's only backing up CHANGES made to files, not backing up every dang thing multiple times, is that right?

But what if I want multiple changes backed up? Is it only keeping the most recent change of the day/week/month or multiples?

I do NOT want TM to delete my old backups, but can't seem to find out how to have it alert me BEFORE I'm running out of space (versus automagically erasing my things like photos that I may only want on my external). Is there a way to turn off those auto-deletes?

I'm coming to the conclusion that TM is great for continuous backup but not for long-term storage, since it deletes long-term storage. Am I right in this or am I missing something?

If this is the case and my exHD is already being used with TM, can I turn TM off and backup only my updates in some other way, or is it already formatted for TM and I'll need to reformat it and do it manually? (Such as copying things over and having it ether replace or make a second copy of things as it goes according to what I want it to do.)

I hope all this is making sense because I feel like I'm talking myself in circles.

Thanks in advance,
Tara

 

[Ivan P]

You're right in assuming it only backs up changes made since the last backup, it does not back up your entire computer each time.

Also I believe, and anyone tell me if I'm wrong, it will still keep the old versions of those files even if it has been updated and re-backed up (for example, if you have a document backed up on January 1, and changed it on January 2, the two different versions of the file will be available on your backup disk, one under each of those dates).

I've always had Time Machine inform me when the backup disk was getting full, prior to deleting any early backups.

Technically, you can turn off Time Machine and manually transfer the files that you want between your Mac and the backup drive as if it were a 'normal' external disk, without having to delete the existing backups.

If there are only certain things you want to be backed up, open up Time Machine preferences, click Options, and you can choose what folders to exclude from your backup. This way, only the items you want to keep constantly backed up will be.

 

[SandboxGeneral]

<snip>

Check out this Wiki on Time Machine.

Time Machine creates a folder on the designated Time Machine volume which is named the current date and time. It then copies all locally attached drives (except for excluded files/folders) to the folder.

Every hour thereafter, it creates a new folder on the designated volume using the same naming scheme, but instead of making another complete copy of the primary hard drive, Time Machine instead only backs up files that have changed and creates hard links to files that already exist on the remote drive.

Also from Apple: Mac 101:

As your backup drive begins to fill up to its capacity, Time Machine intelligently deletes the oldest backups to make room for newer ones (and will alert you if the "Notify after old backups are deleted" option is selected in Time Machine preferences).

 

[TaraW]

Thank you for your responses; it's become a little more clear to me.

Ivan P, I'm not seeing an option to have it notify me as it's getting full. Can you point me in that direction?

Also, I found this:

Time Machine works best if you use your backup drive only for Time Machine backups. If you keep files on your backup drive, Time Machine won’t backup those files and the space available for Time Machine backups will be reduced.

So if I manually add files to the exHD it sounds like it won't update those files, so perhaps that's a work-around for files I don't want changed. But is this is in regards to *files* not folders right?

 

[SandboxGeneral]

Thank you for your responses; it's become a little more clear to me.

Ivan P, I'm not seeing an option to have it notify me as it's getting full. Can you point me in that direction?

Also, I found this:



So if I manually add files to the exHD it sounds like it won't update those files, so perhaps that's a work-around for files I don't want changed. But is this is in regards to *files* not folders right?

It's not going to notify you as the HDD gets full. But it will notify you, if you choose, when it deletes old back ups.