Fresh installation on RH8 - index default error

[shoothub]

FYI, Elasticseach version 7.11 and up is not officially suported:

Graylog 4.x and Elasticsearch 7.11.x?

TL;DR 7.11.x is not officially supported by Graylog. There are a number of issues that it introduces that we’re not prepared to support, and IIRC there are also licensing changes that make supporting 7.11 a challenge.

https://docs.graylog.org/en/4.0/pages/configuration/elasticsearch.html#elasticsearch-versions