How do I run a Scriptrunner script when the JIRA application starts, to reindex Zephyr?

[Alex van Vucht (GLiNTECH)]

I need to reliably make a REST API to ZAPI when JIRA starts, to start a reindex of Zephyr test executions.

This is because I am destroying and creating nodes in a JIRA data center 7.4.2 environment, and Zephyr's indexes aren't backing up to shared home, unlike JIRA's main indexes. 

How can I run a script when a JIRA cluster node starts?

Is there a system event that I can use? The Atlassian Events library doesn't give a clear list of events..  https://docs.atlassian.com/atlassian-event/3.1.3/apidocs/index.html