Hi, this is Gary with MacMost.com.
Today I'm going to answer some of the most frequently asked questions about Time Machine.
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So Time Machine is something we should all be using to back up our Macs.
But you may have some questions about why and how it works.
So first should you be using Time machine to back up your Mac?
The answer is definitely YES.
Hard drives fail.
Computers fail.
Computers are stolen.
Disasters happen.
Having a back up of your data is very important.
But what if you're using iCloud.
I often hear people say, well I'm backing up to iCloud so I don't need Time Machine.
If you use iCloud to store all of your documents, all of your photos then it is true you do
have copies of that on Apple servers.
But it's still useful to have a Time Machine back up to have that stuff backed up to another
drive locally.
Drives are cheap.
So why not have an extra back up of your data.
Plus, Time Machine allows you to go back and look at older versions of your files.
It's very important if you made a change that you regret or if you deleted a file and now
you want it back.
So Time Machine backs up your entire drive.
Everything.
System files, library files, things like fonts and all sorts of settings and preferences.
In fact if your drive fails or if your computer is stolen you can recreate everything on your
computer by restoring from a Time Machine back up.
So what sort of drive do you need?
Well, there are two ways to back up using Time Machine.
One is with the drive directly connected to your Mac.
You can do that with a desktop computer like an iMac or if you have a MacBook but it mostly
sits on your desk and doesn't move around.
In that case any USB3 drive will work.
You can find a ton of them, and they're really cheap, if you look online at sites or go to
a local computer store.
Now if you're backing up a MacBook that moves around a lot and is rarely sitting on a desk,
so you don't want to plug in an external drive all the time, you can connect an external
drive to most wi-fi routers.
They'll have a USB port, you can plug it in, and then you can access that drive as a network
drive.
You can choose that as your back up drive.
What size drive do you need?
Well, a general rule of thumb is to make it at least twice the size of the data you're
backing up.
So if you have a terabyte drive on your iMac and you're using most of it you should have
a 2 terabyte drive, at least.
I would say that at minimum have a 1 terabyte drive.
So even if you have a 250G drive and you're not using a lot of it, drives are cheap, so
why not get a terabyte drive and back it up.
The larger the drive you've got, the more of a history will be kept.
So not only will you have every file on your Mac now but you'll also have a history of
changes to files and files you deleted going back months and even years.
So formatting a Time Machine drive isn't really something you need to worry about.
It's automatically formatted when you choose it to be your Time Machine drive.
It's formatted using the old Apple file system which is all that Time Machine works with
right now.
So I get this question a lot.
Should I buy a SSD or an old fashioned spinning hard drive?
Most of the time a back up is just writing out the back up files to the drive.
Speed really doesn't matter.
So getting a SSD is a waste of money.
In fact if you're connecting to it using USB you're not even using the SSD at its full
speed.
The bottleneck is in the cable not in the drive speed.
So getting a hard drive for a back up is perfectly fine.
So as you make changes to files and delete files and replace them with others what happens
when it fills up?
All it's going to do is start deleting older versions files.
Time Machine is always going to keep around all the files you have currently on your drive
so you have a complete back up for a restore.
It's going to keep as many old versions and old files that have been deleted around as
it can.
So it's common to actually back up more than one computer to a drive when you have a house
of MacBooks.
You've got a drive connected to your network drive and you're using that same drive to
back up two, three, or four MacBooks in your house.
That's normal.
In that case you want to make sure that drive is big enough to handle all of that.
But otherwise if it's a drive connected directly to your Mac you should have one for each Mac.
That way you don't have to disconnect it and move it around.
Drives are cheap so why not have a back up drive for every desktop computer.
Now, this is a big mistake I see people make all the time.
They get this nice new external drive, maybe they've never had an external drive before,
and they think, ooh, I can put other things on it as well.
Drives are cheap.
You should only use your Time Machine back up drive for Time Machine backups.
In fact putting other files on it will sometimes mess up Time Machine which is trying to manage
the files on that drive moving older versions and older files to make room for newer ones.
If you're always putting new things on it or changing things on the drive it could lead
to issues.
So get another external drive if you want to have an archive drive or something like
that.
But how about the opposite.
How about having more than one back up.
You can do this.
You can actually plug in a second drive and assign that as a Time Machine back up drive
as well.
This is commonly done in situations where you're moving the Mac around.
Like if you take a MacBook between home and work you can have a Time Machine back up in
either one.
So setting up Time Machine is pretty easy.
As a matter of fact if you don't have Time Machine setup and you buy an external drive
and you plug it in Mac OS will prompt you asking if you want to use this drive as a
Time Machine drive and then everything just gets set up automatically.
But otherwise you can go into System Preferences, Time Machine and then you can select that
disk as a drive and everything else is pretty automatic.
Time Machine backs up things hourly.
A common question is people say well can I have it do it less?
The answer is you really don't want it to.
Because if you have it do it less that means it's going to be doing more work with each
back up.
An hourly back up is only going to back up things that have changed.
It's an incremental back up.
So it should be fairly quick.
Now there is a way to exclude things from your back up.
You can go into Time Machine, Preferences, you can click Options, and there you can add
exclusions.
This is useful in cases where you have things you know you don't want to back up.
So what if you have an external drive that has some data on it and you want that backed
up as well.
Well Time Machine can back up external drives attached to your Mac.
What you want to do is go into those exclusions and make sure the external drive isn't listed
there.
By default it will probably be added to that list.
So you simply remove it from the exclusions and now Time Machine will back up your internal
drive and that external drive as well.
So Time Machine isn't just for a disaster like if your computer is stolen or the hard
drive fails.
It could also be used to turn back time when you've made a mistake.
For instance what if you accidentally delete a file or a folder full of files and you realize
it a week later.
You can use Time Machine to get those back.
You can even use Time Machine to get back files that you've changed.
So, for instance, you're working with a PhotoShop document.
You make some changes to it and you realize I really want to go back to how the file was
yesterday.
You can use Time Machine to grab that old version of the file.
So restoring a file from Time Machine is a little weird.
What you want to do is go to the location of that file.
Then activate Time Machine and it will give you this view of the folder that allows you
to go back in time.
Select the file and then hit Restore to restore a copy of that file.
You can have it Replace the current file or have it appear as a New File.
If you have any other questions about Time Machine be sure
to ask them in the Comments.