Updating boot partitions required mac
While you’re in Recovery mode, you may also want to verify disk permissions and repair them, repair user permissions, and verify and repair other disks as well.
Again, if you see that the “Repair Disk” function is greyed out and not clickable in Disk Utility, be sure to boot back into Recovery Mode again on the Mac to make it accessible again.
By the way, if you are using a bootable installer drive, you can perform this partitioning process directly from there.
Now that OS X El Capitan is running on the alternate partition but the same Mac, you can easily switch between the two startup drives operating systems by rebooting and holding down the OPTION key – this opens the startup manager before OS X loads, allowing you to choose between which version of Mac OS X you wish to run.
These can be used either if you are logged in in Single User mode (after holding Command-S at startup to drop you to a root terminal prompt instead of loading the OS X interface), or if you are logged in remotely through an SSH connection.
Two options for use in the Terminal are the "diskutil" command, and the "fsck" command.
Do keep in mind that “Verify Disk” will always be available, whether booted from the primary startup volume or not, it’s only the Repair function which, on newer versions of OS X, requires the usage from a recovery disk or another startup disk on the Mac.
There are also alternatives to the Disk Utility program built in to OS X.If for some reason the routine seems stuck (which is rare but may happen), since it is just a checking routine, you can force-quit Disk Utility to halt the check and return your system to a usable state.Unfortunately, formatting errors can happen even if you've just been using your computer in a normal way, so even though your system may be running fine at the moment, it can only benefit from a regular drive check.In a much similar manner, you can also install OS X El Capitan onto a completely separate hard drive, or even an external drive, as long as it’s bootable and that you select it within the installer app target.If at any point you wish to delete El Capitan and reclaim the disk space, you can do so back in Disk Utility by removing the El Capitan partition, but just as before, don’t skip the backup process first.