10.10.4 installer

[Tech198]

After downloading 10.10.4 installer from the Mac App Store and creating usb bootable usb drive. I found i with SSD i needed to remove CoreStorage in order to totally wipe the drive from Terminal..

so i used diskutil cs list to find id then deleted this... instead without rebooting (it was quicker)

This went well, however u cannot install after partition creation, "Reinstall OS X" and then continue option does not work...... I resolved by by rebooting and all is ok...

so my question,, since i used diskutil cs to remove core storage (confirmed both diskutil list, and also DiskUtility showed "Unformatted" why was a reboot required to fix ? I thought diskutil cs command was there to remove. I was booted of usb at the time

Also, why is Core Storage removal only required on SSD, not spinning hard drives.... ? My 500Gig Mac mini went through no problem, and is running Yosemite.

 

[Weaselboy]

I'm not sure where you went wrong. You should have been able to boot from the USB key then from there run the command below in Terminal (substituting the real volume name normally Macintosh HD). Then format with Disk Util and continue with the install.

diskutil cs delete "volume name"

Core storage is not because you were on an SSD. When you install Yosemite the installer looks to see if the machine is a portable, and if it supports AES-NI. If the answer to both is yes, and Bootcamp is not present, it will get converted to CS.