Bad Gateway Error in Kibana 6.8.0

ES 6.8.0 is up and running but while running Kibana error of
[plugin: xpack-main@6.8.0]-Bad Gateway
[plugin: graph@6.8.0]-Bad Gateway
[plugin: spaces@6.8.0]-Bad Gateway

Poll Error Bad Gateway

i am not using xpack feautre in ES and made ES run with default settings with xpack.security.enable: false in elasticsearch.yml file but still getting this error while running kibana.

what's the server.host set as in your Kibana.yml file?

server.host: 0.0.0.0

Is there anything specific about your setup? reverse proxy? Also, can you post complete logs for Kibana? There may be some other issues that are displayed earlier that could trigger this.