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Disable Security Features to Dual Boot OS X - El Capitan

So, I've recently been working on updating/rebuilding my latest little friend (an 11" MacBook Air) to dual boot the latest OS X, El Capitan, and Kali. I'll go over everything in full detail as soon as I can finish the setup, but I wanted to get this out there for anyone else that may stumble upon any issues with setting up rEFInd on an updated mac.

To start, while on Yosemite, I downloaded El Capitan from the App Store, and copied the install files to a USB. From there I preformed my upgrade. This might not be a good option for some people, as I'm sure your mac might be your primary computer... For me, that's not a problem. I tend to keep my essentials on USB drives / cloud storage as I tend to need access from different devices (phone, computer, tablet, etc.).

After preforming a clean install of El Capitan, I headed over to the rEFInd website, download the program and ran the install.sh script... Now, that appears to work, like it did with pervious versions of OS X. However, on reboot...no joy... So, I started down the path to see what went wrong. I go though the manual steps (I won't detail them here because the folks at rEFInd do a good job with that), and I find that everything appears to be as it should be.

Now, the final step in the manual install says to issue the "bless" command. When I attempted to issue the "bless" command, the terminal promptly responded with "bless failed"... Super....

A quick Google took me over to a thread on GitHub where this same issue was seen on BootChamp (see below for the reference). In that thread, I find this little nugget of information pulled form Apple's website:
Note: To safeguard against disabling System Integrity Protection by modifying security configuration from another OS, the startup disk can no longer be set programmatically, such as by invoking the bless(8) command.
After reading though everything, I had my plan of attack:

  1. Boot to recovery using the USB install disk that I created prior to the upgrade (like I said, I like to start fresh)
  2. Pull open the terminal while in recovery mode
  3. Enter the following command
csrutil disable


Now, for some pics for those that may get lost at this point:

Terminal in recovery with command ready to go


From here, I restarted the machine, then finalized the install of rEFInd using the "bless" command (again, detailed in the Manual Install instructions from their website). After that finishes successfully, I run another restart and viola! I'm in business:



References:

rEFInd:
http://www.rodsbooks.com/refind/

GitHub BootChamp Reference:
https://github.com/kainjow/BootChamp/issues/19

Apple's System Integrity Protection:
https://developer.apple.com/library/prerelease/mac/documentation/Security/Conceptual/System_Integrity_Protection_Guide/ConfiguringSystemIntegrityProtection/ConfiguringSystemIntegrityProtection.html

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