How to Migrate from a Very Large Hard Drive to a Very Small Solid State Drive

Solid state drives finally got cheap enough to tempt me to buy one.  But my quandary was this: my old hard drive contained 700+ gigabytes of data, while the new SSD only can accommodate 64 gigabytes.

I figured it out; here is how.  These instructions apply if you have a Mac (I am running OS 10.7 Lion); if you run Windows, you have my sympathies.

The basic idea is to install the operating system and the all your applications onto the SSD, and keep everything else on the old, spinning hard disk.   Your system has to be able to physically accommodate two drives.

  1. Install your new SSD and install the Mac operating system to it using the DVD that came with your computer.
  2. When you are setting up the new operating system, elect to run Migration Assistant and connect the old drive to your computer in some way.
  3. In Migration Assistant, migrate everything except User accounts (uncheck that box).  Odds are, most of your data resides in your User account folders.  In my case, most of my space was consumed by pictures and music in my User folder.
  4. Set yourself up a user account on the new, fresh OS.  I made sure that my username was identical to my username on the old installation.  This might not strictly be necessary.
  5. Make sure your old hard drive is still physically connected to the computer.
  6. After the setup process is complete, go into System Preferences, and then select Users & Groups.
  7. Click the lock to “unlock” the settings.  Type your password to authenticate.
  8. Right-click your name on the left panel, and select “Advanced Options…”
  9. In the “Home Directory” box, you want to tell the operating system the location of your old user account, on the old drive.  Click the “Choose…” button to navigate to it.  Odds are, it will be located at /Volumes/Hard Disk/Users/[your_name].
  10. Click OK.
  11. Repeat as necessary for several user accounts.

Now, your experience should be seamless — I cannot remember if you need to restart, but your entire old user account, including all your files, settings, wallpaper, etc., should look just like it used to.

Your last step now should be to set up Time Machine again for backups.  You will have to set it up again because your primary drive name has changed.  The good news is, Time Machine will still “see” your User account as if it is on your new boot drive, and backups will also be seamless.

If your experience is different, please leave a comment!

2 thoughts on “How to Migrate from a Very Large Hard Drive to a Very Small Solid State Drive

  1. You should check this link before you have to look for it in the wayback machine:

    I have been using this method since I have SSD, I think since Snow Leopard and although it may seem old (as Unix) it continues works like a charm (touch aluminum) even in 10.8.4.

    Just check the man pages because now there’s specific editor to manipulate fstab in Terminal (I still use plain old vi with out complains).

    The best thing of all is that if I make a bootable copy of my boot SSD in any device or partition and I restart from it, there is never a problem with the Users the UUID never changes (so it’s an absolute pointer) -that’s until I delete The Users partition.

    I think continues to be the best way to have the boot & users in a different drives or partitions. And if your user partition goes south, you can always loging as root modify the fstab to point to the new partition and recover using your users directory using your latest regular backup or even time machine.

    Hope it’s useful

Leave a Reply