Too many users feel not happy at all with the Disk Utility in El Capitan since all the useful functions such as Repair disk permissions do not exist any more. How to bring back Disk Utility in Yosemite 10.10 to Mac OS X 10.11 - El Capitan? It is doable in seconds.
Step 1: Download Disk Utility App (from Yosemite 10.10.5) here.
Step 2: Enter the following command lines through Terminal (Found in /Applications/Utilities/)
sudo chown -R 0:0~/Downloads/Disk\ Utility.app
defaults write com.apple.DiskUtilityDUDebugMenuEnabled1
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