Seagate Expansion Mac Time Machine Title Image

Most of us need a Time Machine backup on our Mac.

It’s why I hope you’re here.

Because it’s likely a sensible idea to back up your MacBook regularly. When you’ve bought yourself a Seagate Expansion and you’re wondering how to get it set up with your Mac for a backup.

You’ll find here the help you’ll need.

Seagate Expansion Mac Time Machine Backup In Brief

1. Log and connect your Seagate Expansion’s USB cable.

2. Open System Preferences. Double click Time Machine.

3. Click To Select Disk.

4. Click on your Expansion external drive. Click the Use Disk button.

5. Put a check in the box ‘Backup Automatically’. Your Expansion’s Mac backup will start in a couple of minutes.

And now for the detail.

Seagate Expansion Drive Mac Time Machine (How To Set up)

First check your Expansion drive from Seagate Technology is in the right Mac format for a Time Machine backup.

Expansions come ExFAT or NTFS formatted. And your Mac’s Time Machine backup software doesn’t use either of those file system formats.

If your Expansion external hard drive. Or SSD isn’t in Mac OS Extended Journaled or APFS format.

You’ll first need to format with Disk Utility. Take a look at this article on the site. Seagate Expansion Format For Mac. Click on the linked text to go over to the article. Then come back here when you’re done.

Connecting up your Seagate Expansion to Time Machine is a simple process.

Here goes.

1. Log And Connect Your Seagate Expansion’s USB cable.

You’ll need to be logged into your Mac computer. And plug your Expansion backup drive into your Mac’s USB C port.

In a few moments, your drive will come up on your Mac’s desktop.

Seagate Expansion Drive Icon

2. Open System Preferences. Double Click Time Machine.

You can start up System Preferences through a spotlight search.

Spotlight Search Symbol

Type in System Preferences and double click when it comes up.

Or you can click on the Apple symbol top left of your desktop. And click on System Preferences from the menu that comes up.

System Preferences In Spotlight Search

Scroll down. Then pick Time Machine from the System Preferences window.

Time Machine in System Preferences

3. Click To Select Disk.

When Time Machine starts up you’ll see its pop up window.

Seagate Time Machine 1st Window

On the left hand side, you’ll have a check box for Backup Automatically.

Leave that box unchecked for now.

At the bottom of the pop up screen, you’ll see another check box.

Put a check in that box to show Time Machine in the menu bar at the top of your desktop screen.

On the right hand side of the pop up window click ‘Select Disk’.

You may instead see the message ‘Add or Remove backup disk’. This will come up if your Mac’s already set up with a backup disk. You can click on that option if your Mac doesn’t show ‘Select Disk’.

You’ll then you’re taken to the 2nd Time Machine set up window.

4. Click On Your Expansion External Drive. Click The Use Disk Button.

This 2nd Time Machine pop up window will show you your Seagate Expansion listed under available disks.

You’ll see the name you gave your Expansion drive when you formatted your drive.

Or if you created a partition to back up to, you’ll see the name you gave your partition.

Seagate Time Machine 2nd Window

Click on your Seagate Expansion.

And then click on the ‘Use Disk’ button.

That’s it, your Seagate Expansion is now set up with Time Machine. And you’ll go back to the 1st Time Machine window you saw.

If for some reason your Expansion external drive doesn’t show in the 2nd Time Machine window. Or it’s there but grayed out and you can’t click on it.

It’s because your Seagate backup drive isn’t in the right format for Time Machine.

Did you follow the formatting instructions fully when you hopped over to the formatting post earlier?

Or there is something up with your Seagate drive. And that’s why it’s grayed out. You may need to run Disk Utility First Aid on your drive.

5. Put a check in the box ‘Backup Automatically’.

Now that you’re back at the first Time Machine window, you can put a check in the box to ‘Backup Automatically’. Then you can close Time Machine.

Your Expansion’s Mac backup will start a couple of minutes.

And now your Mac is set to back up automatically each time you plug in your Seagate Expansion.

Be sure to eject your Seagate Expansion from your Mac when your backup has finished.

And you’re ready to put your Seagate Expansion away.

Checking On The Progress Of Your Seagate Expansion’s Backup

Look at the top of your Mac’s desktop and click on the Time Machine icon.

Time Machine At Top of Desktop

From the menu that comes up, you’ll see the progress of your backup. And right now, it’ll say preparing backup, or searching for changes.

Seagate Time Machine Preparing Backup

And as your backup progresses, you’ll see how much your Mac has backed up to your drive. And how much you’ve left to backup.

Be patient.

If this is your first backup and you’ve large internal disk drives, your Mac could say preparing backup for a while.

Eject your Seagate Expansion when your backup completes.

To Start A Backup Right Away To Your Seagate Expansion

Click on the Time Machine icon on your Mac’s desktop.

Time Machine At Top of Desktop

Then select ‘Backup Now’ from the menu.

Time Machine Backup Now

And your Mac will back up right now.

Useful if you’ve made a lot of changes and want to back them up to your Seagate storage device right now.

How Does Time Machine Organize Your Backup To Your Seagate Expansion

While you’ve your Seagate Expansion external drive plugged into your Mac.

Your Mac computer will back up on this schedule.

The first backup is of everything on your Mac other than your Mac OS X. You can’t backup. Or restore your Mac OS X (operating system) through Time Machine these days.

After that first backup. Every hour for the first 24 hours, your Mac backs up your changes.

Your Mac will still backup any changes each hour but will keep daily backups for a month.

After that Time machine keeps weekly backups for each month.

Your Time Machine backups are actually incremental forever.

And that means after your first backup Time Machine backs up only your changes. That means anything new you’ve put on your Mac, MacBook Pro or MacBook Air.

And if your Seagate Expansion external drive runs out of room for your backups. Then your Mac will delete the oldest backup to make room for your newest backup.

Seagate Expansion Mac Time Machine Frequently Asked Questions

What Size Seagate Expansion Drive For A Backup With Time Machine?

A rule of thumb is, if your Mac has a 250GB internal drive you want to back up. And your internal drive is 50% full.  Then to do your first backup you’re going to need 125GB.

If you know that the kind of work you do on your Mac each day means a lot of changes.

Those changes get backed up. So, each day your back up drive will need room for 20GB or more.

You can then see that it’s likely that you’ll want a 500GB SSD (Solid State Drive) Expansion drive.

You’ll want room on your drive for your initial backups. Plus, the changes you expect and the number of backups you want to keep. Also think about how far you want to be able to go back and restore a file from your backup?

If you’re happy to use a Seagate Expansion external hard drive for your backup. Because you don’t need the fastest backups. Then the cost of 1GB drives mean you can get one of those and be happy you’ll be able to back up to it for a while.

It’s also a good idea to have two external drives you back up to. You can set up a second drive in Time Machine and just alternate backing up to each drive.

That way, if you do get a failure on one Seagate drive, you have a backup on a second.

A great idea if your files are important to you and you really can’t afford to lose them.

CLICK HERE: When You Want a Second Drive Read A Review On the Seagate Expansion On Mac

How Do You Format A Seagate Expansion Drive For Time Machine?

You’ll use software that’s part of your Mac operating system, Disk Utility to format your Seagate storage.

You’ll need your Seagate Technology Expansion drive formatted to APFS (Apple File System). Or Mac OS Extended (Journaled) file system. With a GUID Partition Map as the scheme.

Pick Mac OS Extended Journaled for compatibility with older Mac OS X operating systems. As Mac OS only supported APFS for a Time Machine backup since Big Sur.

In Closing

I hope this blog was helpful in showing you how to use your Seagate Expansion external drive for a Mac Time Machine backup.

Get 2 so you can alternate between the two backups and feel secure that should you need it. You’ve another copy of your data on another drive.

While you’re here, do take a look at our other Seagate Expansion articles on the site.

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