The installation directions for marvel -- a plugin for elastic search -- is very scant and unnecessarily indirect. The clearest instructions I found on how to install the marvel plugin through homebrew was on Twitter! Twitter! Why?! Anyways, to install marvel via brew, you can do this:
brew update
brew upgrade elasticsearch
cd /usr/local/Cellar/elasticsearch/<whatever version>
bin/plugin -i elasticsearch/marvel/latest
As of version 2.3.4, inside of the elasticsearch directory, you'll find there is a
libexec/bin
folder. That contains the script you needHowever, after I did that, my cluster health dropped to yellow and Marvel would not launch. This was on a brand-new install with no data in the index.