How to clone a drive on iMac?

Here's a simple approach:

1. Buy an external enclosure and put your old drive in it.
2. Install your new drive in your Mac.
3. Boot from your old (external) drive by holding the Option key on startup.
4. Use Carbon Copy Cloner to clone the old (external) drive to the new (internal) drive.
5. Boot from the new internal drive.
6. Your now running on your new internal drive and your old drive is now an external drive, useful for backups or additional storage.

 

Have you tried making a Time Machine back up of your original drive and then just putting it back into the new one via Time Machine? Simpler.

 

You can use Disk Utility instead of CCC. I used it to clone my smaller HDD to my larger SSD before I switched them.

 

You asked me hwo to do it, I gave you a way. I would advise you to get an external drive and make yourself a back up. Not having one is begging for information loss if something goes wrong.

 

NEVER attempt any kind of "whole disk" manipulation without a backup. You NEED another drive for your backup. If you're putting a 1TB drive in your Mac, then I would recommend at least a 2Gb or 3Gb external for a Time Machine backup.

There's no point putting Time Machine backup on the same hardware device as the source data. Because when the drive fails, you still lose everything.

 

You can exclude system files and other folders from TM backups. But given that system files are generally not often written to and altered, the size penalty for storing them is not that great.

You will find many posts here along the lines of "I accidentally deleted one system file/Apple app. Do I have to reinstall the whole OS ?"

You CAN clone your old hard drive onto your new one, and it should work. But you don't want to attempt an operation of this sort without a backup in case something goes wrong.

You need to boot from another volume -- the Restore Partition may well do -- and then use Disk Utility to restore the contents of the old drive ono the new disk.

 

You can do what you need to do by the following procedure. You WILL need one small item of "additional hardware", but a very useful piece of hardware -- read on.

The best way to do this is to spend about $30 and buy an external USB3/SATA "docking station". Go to amazon.com, enter "USB3 SATA dock" in the search box, and you will find many to choose from. Just pick one that's cheap that you like.

Also, download CarbonCopyCloner -- you can use it free for 30 days.

Once you have the dock, and the new drive, do this:

Put the bare drive into the dock, connect it to the iMac, power-up.

Launch Disk Utility and initialize the new drive. It should now mount on the desktop.

Launch CCC.

On the left, choose your source drive (iMac internal).

On the right, choose your target drive (WD).

Choose to backup everything.
(NOTE: if you use a version of the OS that has a "recovery partition", go to CCC's preferences to choose whether or not to clone the recovery partition first).

Let CCC do it's thing.

When finished, TEST YOUR CLONE by doing this:
- Restart
- As soon as you hear the startup sound, hold down the option key and KEEP HOLDING IT DOWN
- In a few moments, the startup manager will appear
- Use the pointer to select your external drive, then hit return
- The iMac should boot from the external cloned drive
- When you get to the finder, VERIFY that you are booted from the clone by checking "About this Mac" under the Apple menu.

If all looks good, you have created a fully-bootable clone -- an exact copy of your internal drive. That's what you need.

Now it's time to do the physical "drive swap" for the iMac.

When done, you can use the OLD drive as your "bootable backup", using the USB/SATA dock. (which will become handy to have around in future years)