Issues with Changelog 0087 - upgrade to ES 6

Hi Amit, the reindex seemed to kick off but I ran into another issue.
Please take a look at these logs and let me know your thoughts?

This was on the first re-index (apps):

The result of running
cchq <env> run-shell-command elasticsearch "grep '<Task Number>.*ReindexResponse' /opt/data/elasticsearch*/logs/*.log"
From the control machine was:

I then checked the es log using cat and found this:

I tried again after that:

once again the runshell command:

and the es log: