git clone git@github.com:settlin/mongo-to-elastic.git
node index.js /path/to/config.js
or
npm run sync -- /path/to/config.js
The sync does not update removals, and simply works on timestamps (createdAt and updatedAt fields) present in your mongo documents.
See a relative link for details.
The nifty backup.sh backs up entire elastic db to aws s3. It is a very simple script depending on elasticdump and aws cli and you can tweak it for your personal use.