Where to find config/root-ca.pem?

[chhaosh]

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I am referring https://opendistro.github.io/for-elasticsearch-docs/docs/trace/data-prepper/ to configure the data-prepper
My ES cluster is OpenDistro ES Cluster with demo security configuration, I am wondering where I can get cert: "config/root-ca.pem", I tried to use /usr/share/elasticsearch/config/root-ca.pem and put it under data-prepper pod, but it complains
Caused by: javax.net.ssl.SSLPeerUnverifiedException: Host name 'opendistro-es-client-service' does not match the certificate subject provided by the peer (CN=node-0.example.com, OU=node, O=node, L=test, DC=de)

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[chenqi0805]

@chhaosh Thank you for trying out data-prepper. The PEM file can be generated by OpenSSL with hostname matching the common name (CN). This doc might be useful: https://opendistro.github.io/for-elasticsearch-docs/old/0.9.0/docs/security/generate-certificates/