How Time Machine works
Before explaining to you how to use Time Machine, it seems only right to tell you, in detail, what it is about.
Well, if you were not aware of it, Time Machine is the application that allows you to create a automatic backup (but possibly also manual) of all data on the computer, including applications and settings, on a external hard disk.
The backups in question can then be used for recover deleted data by mistake, as well as old versions of files and / or folders modified or, even, for restore the entire system to a previous state.
It is good to keep in mind that backups on Time Machine are performed in two different ways: the first time the data on the computer is saved, a backup is made complete of the entire system and it takes more time for this to complete (the actual duration depends on the quantity of files). Subsequently, the backups become of type incremental, so they are faster and only save the new files and / or update the files that have undergone changes.
Backups are sorted by time and managed according to Free space: The backups of the last 24 hours, the daily ones of the last month and the weekly ones of all the previous months are kept. Older backups, however, are automatically deleted when disk space runs out.
Another thing to keep in mind is that, considering that to take advantage of Time Machine you need to have an external storage disk, the ideal would be to use one two to four times larger relative to the space occupied by files on the hard drive, so that you can have a sufficiently large backup history before Time Machine starts deleting older data due to out of space.
Still on the subject of external disks, if you don't have one yet and you don't know which device to go to, I suggest you read my buying guide dedicated to this type of product. You will find many useful tips on this.
How to use Time Machine on Mac
Having made the necessary clarifications above, let's get to the real heart of the matter and let's find out, in practice, how to use Time Machine on Mac. You will find everything below, from the preliminary operations that must be carried out to the next steps. It is much simpler than you might think, fear not.
Preliminary operation
The first fundamental step you need to take to start using Time Machine on your Mac is to connect the external hard drive to the computer to be used for backup, via cable.
Once connected, if the hard drive in question is already formatted with the file system Mac OS Extended journaled, that is the one capable of hosting Time Machine data, you will see a window on the macOS desktop through which you will be asked what you intend to do. If this is your case, you can proceed directly with the backup configuration, as I will explain in the next step.
On the other hand, if the disk connected to your Mac is not formatted with the proper file system, you will have to fix it first. To do this, you can use Disk Utility: the application pre-installed on all Macs and responsible for managing disks and partitions. To use it for your purpose, select the relevant one icon (Quella with l 'hard drive and stethoscope) found in the folder Other of Launchpad.
In the window that appears, then choose, through the left menu, the external drive which is your intention to format. If you don't see the list of disks on the left, click the button with the window present at the top left and select the item Show sidebar give the menu to compare.
Next, click the button Initialize located at the top, choose the voice option Mac OS extended (journaled) give menu to tendin Size, type the name you intend to assign to the external drive in the field Your name (Eg. time Machine), make sure that at the drop-down menu Scheduling the option is selected GUID Partition Map (if not, you can do it yourself) and click on the button Initialize, to start formatting the hard disk.
The disk formatting procedure should take a few seconds. Once completed, you will see an appropriate notice. To close it, click the button end.
After formatting the drive, you can choose to take advantage of the latter as well as network disk, connecting the device to the router. If so, if you own a Apple's AirPort Extreme 802.11ac or a Time Capsule, connect the hard disk to the USB port of the device, open AirPort Utility on the Mac, by selecting the relevant icon (Quella with him Wi-Fi cleats) in the folder Other of Launchpad and click on device name.
Then click on button to unlock the device and enter the Password of the latter (if necessary). Then proceed to click again on router name on your pulse Modification in the box that appears on the screen.
In the window that opens, click on the tab Discs, select the disk or partition you want to back up Time Machine on from the pane Partitions, check the box next to the item Enable file sharing and press pulsating Update located at the bottom right.
Stai using a other brand routers, after connecting the external hard drive to the latter and after making sure that your Mac is connected to the network generated by it, you can proceed as follows: open the Finder on your Mac, select the relevant one icon (Quella with the smiley face) placed on the Dock bar and verify that the disk is listed among those in the left sidebar.
How to use Time Machine with external hard drive
Immediately after connecting a properly formatted external hard drive to your Mac, you should see another window asking you if you want to use the disk for making backups with Time Machine. In that case, click on the button Use as a backup disk, in order to start creating the backup of your computer immediately.
Through the above window, before clicking on the button to proceed with the use of the external disk for Time Machine, you can also decide whether to encrypt your backups or not, by affixing or leaving unchecked the box next to the option Backup disk encryption. This way, you can set a Password to protect your data, but keep in mind that if you lose it, if necessary, it will be impossible to restore everything.
If you do not see any warnings or if you are using a hard drive connected to the network, click on theTime Machine icon (Quella with l 'clock and arrow) that you find in the upper right part of the screen and select the item Open Time Machine preferences. If the Time Machine icon is not visible on the menu bar, to fix it, click on theSystem Preferences icon (Quella with the ruota d'ingranaggio) that you find on Dock bar, click on the item time Machine in the window that appears and check the box next to the wording Show Time Machine in the menu bar present in the next screen.
In the window that is now shown on your desktop, click on the button Select disk and select il external drive to use for backup; then choose whether or not to encrypt the backups, by ticking or leaving the relative option unchecked, and confirm your choice by pressing the button Use disk.
Note that in the specific case of network disks, you may also be asked for confirmation to establish the connection. If so, click the button Connect, enter the password to access the router and press the button again Connect.
Note that, by default, Time Machine makes backups automatically. So, leaving the external hard drive always connected to the Mac (via cable or network), the system will constantly copy all the necessary data without you having to do anything else. On the other hand, if you disconnect the external hard drive from the computer, the backup will be performed again, always automatically, every time you connect the device again.
If you wish, however, you can turn off the option to automatically make backups, so you can decide when to perform them and when not. To do this, open the Time Machine window as I explained earlier and remove the check from the box next to the item Back up automatically, which you find on the left.
Later, you can make backups on "command" by clicking on theTime Machine icon at the top right of the screen and selecting the item Back up now annessa to the menu che vedi comparire.
Both in the case of automatic and manual backups, when the data saving operation is in progress, theTime Machine icon at the top right of the screen shows an additional arrow and clicking on it will show you the amount of written data, in the menu that will open
I also point out that, always through the menu visible after clicking on theTime Machine icon, you can find out when the last Backup was made, under the heading Last backup on "disk name".
Do you want to exclude certain drives and / or specific files and folders from the backup? You can do this by accessing the Time Machine preferences, as I explained to you in the previous lines, then clicking on the button options at the bottom right, by pressing the button capacitor positive (+) lead and selecting the path of your interest. You can also decide to to exclude applications and system files, by checking the box next to the appropriate item at the bottom. To confirm the changes, proceed to press the button Save.
Once you have configured the use of Time Machine, to restore files from an existing backup, click on theTime Machine icon at the top right of the screen and select the item Enter Time Machine from the menu that opens. Through the screen that will be shown to you later, you can select from time bar on the right the date of the backup to be traced back and using the Finder that the file and / or folder to restore will be shown in the center.
Once you have found the item you want to recover, select it and press the button Restore at the bottom, to restore it to its current position. To save the file or folder in a different location, instead, right-click on it and choose, from the context menu that opens, the item Reset [file or folder name], then indicates the folder in which to save it.
How to use Time Machine after format
As I had anticipated, it is also possible to use Time Machine to restore the operating system in its entirety and then restore the Mac to a previous state, even after formatting the computer. How you do it? I'll explain it to you right away.
For starters, start your Mac in recovery mode. To do this, turn off your computer, turn it back on and hold down the keys cmd + r on the keyboard until the appears bitten apple logo on the screen. Afterwards, you will see the macOS recovery mode menu appear. So choose the option Use In your lenguagen as your primary language and click on arrow, to continue further.
At this point, connect the hard disk with the Time Machine backup to the Mac (if you have not already done so), select the option Restore from Time Machine backup, award your bottone Continue (twice) and select the disco of your interest. Once you have done the above steps, press the button again Continue, select the backup date to restore and press the button again Continue.
Finally, select the destination disk backup (i.e. the Mac hard drive), click on the button Unlock, type the administration password of the computer, press the button Restore and wait for the recovery process to be completed, bearing in mind that the procedure could be quite lengthy, depending on the amount of data to be recovered.
How to use Time Machine