mine 13" MacBook Pro has 500GB internal tough drive space, and I purchase a 1TB external HDD to usage as mine Time device backup. I just read native many short articles that the backup should be around 2 to 3 times the size of my tough drive, however I feel choose 1TB will never ever be fill up, and also in fact, leave a many of free space.

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I know that Time maker takes a snapshot of my entirety system and stores it in the back-up drive. Yet say, for example, only about 120GB of my internal HDD is in use. Climate it"ll only take a snapshot that"s around 120GB in size, and also while the same picture will thrive over time together I take much more recent snapshots of my system, that will never go past 500GB because that"s the maximum dimension of my inner HDD. Or perform I have actually it wrong? exactly how does Time device work, really?

I"m asking this due to the fact that I want to understand if I should use a separate external HDD for storing mine actual files.

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inquiry Sep 3 "13 in ~ 13:43

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You probably want to examine out this website because that the many information, however here is the answer to her question, quoted indigenous the website above:

1. How big a drive carry out I need for Time Machine?

A general "rule that thumb" is, to store a reasonable "depth" the backups,Time an equipment needs 2 to 4 times together much room as the data it"sbacking-up (not have to the entire size the your interior HD). Besure to include the dimension of the data on any other drives/partitions youwant to earlier up.

But this varies greatly, relying on how you usage your Mac. If youfrequently add/update lots of big files, then even 5 times may notbe enough. If you"re a light user, girlfriend might be able to get 1.5 timesto work, however that"s topic to problems any time a big backup isneeded.

And, of course, the bigger the drive, the much more old backups TimeMachine can keep for you. A drive that"s too small may only have actually roomfor a couple of weeks (or even days) the backups.

Unfortunately, it"s rather hard to predict, and also most the us have atendency to add an ext and an ext data to our solution over time, so if indoubt, gain a bigger one than you think you require now.

Also, there room some OSX features and 3rd-party applications that takeup huge amounts of backup space, for assorted reasons. Check out question9 because that details.

This is a trade-off between room and exactly how long Time maker can keepits backups, because it will, by design, at some point use all the spaceavailable. However it won"t simply quit backing-up once it runs out: itstarts deleting the earliest backups therefore it deserve to keep making brand-new ones.Thus, the much more space the has, the much longer it have the right to keep her backups.

If your backup disk is ~ above the tiny side, and Time device needs come doa very huge backup, either due to the fact that you"ve included or changed a lot ordone something like an OSX update since the previous backup, girlfriend mayget one of the message in Troubleshooting items #C4 (which onedepends on specifically what happened, and also which version of OSX you"re on.)

My Answer

Then it"ll only take a picture that"s around 120GB in size, and while that same snapshot will flourish over time as I take much more recent snapshots of mine system, it will never ever go past 500GB since that"s the maximum size of my interior HDD.

No, no quite. The 1 TB hard drive will it is in filled up because Time machine keeps your backups and also deletes them once your hard drive is filled. There is much more than one back-up stored on that tough drive. As stuffe discussed as well, Time device allows you to reclaim to a previous backup, due to the fact that Time machine may save 7 or 8 backups on that 1 TB difficult drive.

I"m questioning this since I want to know if I have to use a separate exterior HDD because that storing my actual files.

Yes, girlfriend should. You have to be dedicating a drive to Time Machine. Right here is the quoted answer native 3 in the website I attached above:

3. Can I use my Time an equipment disk for various other stuff?

Yes. Time device will not delete something you put there. Yet it"snot a great idea to placed anything else vital on the very same physicaldrive, uneven you earlier it up elsewhere. Once (not if) that drivefails, girlfriend risk shedding it.

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If you want to do this anyway, it"s much, much much better to partition anexternal drive right into 2 (or more) parts, additionally called volumes. Assignone come Time Machine, because that its exclusive usage for backups; use the otherpartition(s) but you want. To use a new drive, or one you don"tmind erasing, see concern #5. To add a partition come an existingdrive that already has data top top it, see concern #6.