Fluentd is unable to forward logs to external ipv6 Elasticsearch instance

Issue

• Unable to send logs to external Elasticsearch using IPv6 with Fluentd as collector.

• Collector pods stream below errors continuously:

  2023-06-29 16:55:05 +0000 [warn]: [elasticsearch_secure] failed to flush the buffer. retry_times=5 next_retry_time=2023-06-29 16:55:35 +0000 chunk="5ff478dd6b35c5b24fccf3c705fc07e2" error_class=Fluent::Plugin::ElasticsearchOutput::RecoverableRequestFailure error="could not push logs to Elasticsearch cluster ({:host=>nil, :port=>nil, :scheme=>\"fd00\", :user=>\"elastic\", :password=>\"obfuscated\"}): no implicit conversion of nil into String"
  2023-06-29 16:55:05 +0000 [warn]: suppressed same stacktrace