Upgrade PhraseApp On-Premise from version 2.x to 3.x
For the new version PhraseApp On-Premise the required Elasticsearch version has changed. Before you can upgrade PhraseApp On-Premise from Version 2 to 3 you have to Setup Elasticsearch >= 6.0.1. A new index will be generated automatically.
Also the environment variable naming has changed from
ELASTICSEARCH_URL. So before upgrading you have to change the name and set this to your new Elasticsearch host adresse.