We recommend installing OpenSearch on RHEL- or Debian-based Linux distributions that use [systemd](https://en.wikipedia.org/wiki/Systemd), such as CentOS, Amazon Linux 2, and Ubuntu (LTS). OpenSearch should work on many Linux distributions, but we only test a handful. We recommend Red Hat Enterprise Linux 7 or 8, CentOS 7 or 8, Amazon Linux 2, Ubuntu 16.04, 18.04, or 20.04 for any version of OpenSearch.
The OpenSearch ditribution for Linux ships with a compatible [Adoptium JDK](https://adoptium.net/) version of Java in the `jdk` directory. To find its version, run `./jdk/bin/java -version`. For example, the OpenSearch 1.0.0 tarball ships with Java 15.0.1+9 (non-LTS), OpenSearch 1.3.0 includes Java 11.0.14.1+1 (LTS), and OpenSearch 2.0.0 includes Java 17.0.2+8 (LTS).
OpenSearch 1.0 to 1.2.4 is built and tested with Java 15, OpenSearch 1.3.0 is built and tested with Java 8, 11 and 14, and OpenSearch 2.0.0 is built and tested with Java 11 and 17.
To use a different Java installation, set the `OPENSEARCH_JAVA_HOME` or `JAVA_HOME` environment variable to the Java install location.
OpenSearch Version | Compatible Java Versions | Bundled Java Version
