Hello,
I use ELK on my server. I have indexes (created by logstash).
When we request for mapping on index (with http) => "logstash-2019.05.27/_mapping"
We have response:
{"error":{"root_cause":[{"type":"type_missing_exception","reason":"type[[logstash-2019.05.27]] missing","index_uuid":"_na_","index":"_all"}],"type":"type_missing_exception","reason":"type[[logstash-2019.05.27]] missing","index_uuid":" *na* ","index":"_all"},"status":404}
Elasticsearch release 6.7.0
Below its the output part of logstash:
output { stdout { codec => rubydebug } elasticsearch { hosts
=> "elasticsearch:9200" index => "logstash-%{+YYYY.MM.dd}"manage_template => false } }
Example of problem on grafana
Except that mapping error all functionalities are working fine, i have response on search request. May be i miss something on elasticsearch configuration or logstash pipeline. If someone has an idea 
Thanks