Future versions of Elasticsearch will require Java 11； your Java version from [/usr/java/jdk1.8.0_..

es@MEPRDAPP01:/es/opt/elastic/elasticsearch-7.14.1> sh start.sh  warning: usage of JAVA_HOME is deprecated, use ES_JAVA_HOME Future versions of Elasticsearch will require Java 11; your Java version from [/usr/local/java/jre] does not meet this requirement. Consider switching to a distribution of Elasticsearch with a bundled JDK. If you are already using a distribution with a bundled JDK, ensure the JAVA_HOME environment variable is not set. 

es@MEPRDAPP01:/es/opt/elastic/elasticsearch-7.14.1> java -version java version "1.8.0_221" Java(TM) SE Runtime Environment (build 1.8.0_221-b11) Java HotSpot(TM) 64-Bit Server VM (build 25.221-b11, mixed mode) 

# use elasticsearch jdk ES_JAVA_HOME="/es/opt/elastic/elasticsearch-7.14.1/jdk"