How to set up a 1TB iMac from a 2-Hard Drive setup with 1.25TB of info?

[Turnpike]

What would be the best way to set up an iMac Pro (which has a 1TB HD) coming from a 2011 iMac with a 1TB Hybrid drive and a 256 SSD?

I'm getting a Fire Wire to Thunderbolt adapter to use Target Disk Mode to make the transfer as quick as possible, but will the automatic set up just merge the info of the two HD's and then tell me which folders there wasn't room for?

If anyone's familiar with what will happen or what problems I'll run into I'd appreciate your input. Thanks!

 

[BrianBaughn]

I'm not sure what will happen but I suspect the process will run for a either a short or very long time and then tell you it can't be completed…leaving you to start over.

First comes the debate of how much space should be left free on an SSD in a Mac these days. You can shoot for roughly 10% free space and probably be doing the SSD a favor. If that's acceptable in your case you would want to offload around 350GB of data from the old machine to an external drive and then attempt the migration.

How you then manage your data externally will be another decision.

 

[Fishrrman]

How much of the 2011's drive is "used"?

How to find this out (the right way):
Boot the 2011 iMac, get to the finder.
Click ONE TIME on the iMac's (fusion) drive icon to select it.
Bring up the "get info" box (command-i)
In "General", what is the "xxGB" in "used" ???

My recommendation:
BACK UP the 2011 drive to an external hard drive.
I recommend using SuperDuper for this job (free to download and use).

Are you "starting from scratch" with the iMac Pro?
By that, I mean when you first boot it, do you get the "choose your language" setup screen (same as you'd get with a new Mac)?

Then, as soon as you boot (before going further), connect the backup.
Then start clicking through setup.
Setup will ask if you wish to migrate data, YES, do this.
Give setup assistant time to "digest" everything on the backup.
SA will present you with a list of stuff to migrate.
You can "pick and choose" from this list, or (if it will all fit), just migrate it all.

Good luck.