omebrew's sbin was not found in your PATH but you have installed formulae that put executables in /usr/local/sbin. Consider setting the PATH for example like so: echo 'export PATH="/usr/local/sbin:$PATH"' >> /Users/jcheng/.bash_profile

Example: Warning: Homebrew's sbin was not found in your PATH but you have installed formulae that put executables in /usr/local/sbin.

export PATH="/usr/local/bin:$PATH"
source ~/.bash_profile