Formatting iMac with Fusion Drive

I just installed OS X 10.8.4 for the second time on my "homemade" Fusion Drive. I remember that I specifically wanted to erase the disk before the second install, and I had no problem doing so from the installer program. I just don't remember whether I had to go to the Tools menu or not to get the Disk Utility...

I don't think you'll have any trouble.

i think there will be no need for fresh install....i think with maveriks install you cand do a fresh one

Serban said:

i think there will be no need for fresh install....i think with maveriks install you cand do a fresh one

Click to expand...

You will be able to do a fresh or an upgrade install of 10.9. You can use a free utility like LDM (link) that creates a bootable USB flash drive with Mavericks on it, provided you have the Mavericks installer downloaded from the MAS. I've used the old build last year of LDM to fresh install ML and it worked like a charm.

I'd like to know that too. How do you format 2 drives at the same time. Because it's combined into one drive.

ifraaank said:

Hi!

When new operating systems gets released, I like to do a fresh install on my computers.

I was wondering, how does it work, when I'm going to install Mavericks on my iMac with Fusion Drive? Can I just format the drive as normally, and it'll install the operating system on the SSD part of the Fusion Drive? Or would I need to do something special in order to make it function like it does now?

//ifraaank

Click to expand...

I think the Fusion Drive contains the OS from the start, and then over time, it moves other data onto it that you use a lot.

henry72 said:

I'd like to know that too. How do you format 2 drives at the same time. Because it's combined into one drive.

Click to expand...

It's not any different than you're used to with a regular hard drive. Just select the Machintosh HD (your Fusion Drive) in Disk Utility and press "Erase".

n-evo said:

It's not any different than you're used to with a regular hard drive. Just select the Machintosh HD (your Fusion Drive) in Disk Utility and press "Erase".

Click to expand...

Thanks for your reply. But my 3TB Fusion Drive is a bit strange after I installed BootCamp.

2 Macintosh HD? I'm confused. I've done a research on Google and people are having similar problem with their 3TB FD.

henry72 said:

Thanks for your reply. But my 3TB Fusion Drive is a bit strange after I installed BootCamp.

2 Macintosh HD? I'm confused. I've done a research on Google and people are having similar problem with their 3TB FD.

Click to expand...

You have two different things with the name "Macintosh HD". Looking at the left pane and judging from my FD (homemade) setup, the top "Macintosh HD" is a Logical Volume Group, which is like a pool of available Logical Volumes. The lower "Macintosh HD" and "BOOTCAMP" are Logical Volumes.

Logical Volumes are new with Core Storage (I believe). You can manipulate them just like physical volumes (like a HDD partition). Just pretend they are partitions.

I've noticed with my setup that I can't change the name of the Logical Volume Group with the Disk Utility.app, but can change the Logical Volume name. So, you could easily change the "second" Macintosh HD name to something else, like "Main Drive". Alternatively, you can probably change the LVG name using Terminal commands, but I'm not sure of the correct parameters at the moment.

Hope that helps some.