Now that El Capitan PB1 is released if you want to make a bootable usb, format an 8 GB or preferably a 16 GB USB3 drive* which should be called Untitled and formatted as Mac OS Extended (Journaled). The installer should be called Install OS X El Capitan Public Beta.app and should be in your Applications folder.
Run this in terminal and wait about 20 minutes:
sudo /Applications/Install\ OS\ X\ El\ Capitan\ Public\ Beta.app/Contents/Resources/createinstallmedia --volume /Volumes/Untitled --applicationpath /Applications/Install\ OS\ X\ El\ Capitan\ Public\ Beta.app --nointeraction
You can boot up from it by selecting it from the startup manager you get when starting your computer and holding down the option key.
If the installation creates a core storage logical volume you can revert it to get partitions back to normal by running these 2 commands in terminal.
diskutil cs list
and then
diskutil coreStorage revert lvUUID
where lvUUID is the last lvUUID reported by the previous Terminal command.
Then restart for everything to get back to normal after you have run these commands in Terminal.
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* - note if your usb is too slow or too small you may get an error "Mount of outer dmg failed" because it did not copy over the invisible files that make the usb bootable. So it is better to use a 16GB USB3 rather than a 8GB or USB2.
Run this in terminal and wait about 20 minutes:
sudo /Applications/Install\ OS\ X\ El\ Capitan\ Public\ Beta.app/Contents/Resources/createinstallmedia --volume /Volumes/Untitled --applicationpath /Applications/Install\ OS\ X\ El\ Capitan\ Public\ Beta.app --nointeraction
You can boot up from it by selecting it from the startup manager you get when starting your computer and holding down the option key.
If the installation creates a core storage logical volume you can revert it to get partitions back to normal by running these 2 commands in terminal.
diskutil cs list
and then
diskutil coreStorage revert lvUUID
where lvUUID is the last lvUUID reported by the previous Terminal command.
Then restart for everything to get back to normal after you have run these commands in Terminal.
----------------------------------------------------------------
* - note if your usb is too slow or too small you may get an error "Mount of outer dmg failed" because it did not copy over the invisible files that make the usb bootable. So it is better to use a 16GB USB3 rather than a 8GB or USB2.
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