Introduce ES_JAVA_HOME (#68954)

This commit introduces a dedicated envirnoment variable ES_JAVA_HOME to
determine the JDK used to start (if not using the bundled JDK). This
environment variable will replace JAVA_HOME. The reason that we are
making this change is because JAVA_HOME is a common environment variable
and sometimes users have it set in their environment from other JDK
applications that they have installed on their system. In this case,
they would accidentally end up not using the bundled JDK despite their
intentions. By using a dedicated environment variable specific to
Elasticsearch, we avoid this potential for conflict. With this commit,
we introduce the new environment variable, and deprecate the use of
JAVA_HOME. We will remove support for JAVA_HOME in a future commit.

.ci/os.sh

@@ -48,6 +48,7 @@ else
 fi
 
 sudo bash -c 'cat > /etc/sudoers.d/elasticsearch_vars'  << SUDOERS_VARS
+    Defaults   env_keep += "ES_JAVA_HOME"
     Defaults   env_keep += "JAVA_HOME"
     Defaults   env_keep += "SYSTEM_JAVA_HOME"
 SUDOERS_VARS
@@ -63,6 +64,7 @@ sudo mkdir -p /elasticsearch/qa/ && sudo chown jenkins /elasticsearch/qa/ && ln
 sudo -E env \
   PATH=$BUILD_JAVA_HOME/bin:`sudo bash -c 'echo -n $PATH'` \
   RUNTIME_JAVA_HOME=`readlink -f -n $RUNTIME_JAVA_HOME` \
+  --unset=ES_JAVA_HOME \
   --unset=JAVA_HOME \
   SYSTEM_JAVA_HOME=`readlink -f -n $RUNTIME_JAVA_HOME` \
   ./gradlew -g $HOME/.gradle --scan --parallel --continue $@

Vagrantfile

@@ -461,6 +461,7 @@ def sh_install_deps(config,
     ensure expect
 
     cat \<\<SUDOERS_VARS > /etc/sudoers.d/elasticsearch_vars
+Defaults   env_keep += "ES_JAVA_HOME"
 Defaults   env_keep += "JAVA_HOME"
 Defaults   env_keep += "SYSTEM_JAVA_HOME"
 SUDOERS_VARS

buildSrc/src/main/java/org/elasticsearch/gradle/testclusters/ElasticsearchNode.java

@@ -728,7 +728,7 @@ public class ElasticsearchNode implements TestClusterConfiguration {
         Map<String, String> defaultEnv = new HashMap<>();
         // If we are testing the current version of Elasticsearch, use the configured runtime Java, otherwise use the bundled JDK
         if (getTestDistribution() == TestDistribution.INTEG_TEST || getVersion().equals(VersionProperties.getElasticsearchVersion())) {
-            defaultEnv.put("JAVA_HOME", BuildParams.getRuntimeJavaHome().getAbsolutePath());
+            defaultEnv.put("ES_JAVA_HOME", BuildParams.getRuntimeJavaHome().getAbsolutePath());
         }
         defaultEnv.put("ES_PATH_CONF", configFile.getParent().toString());
         String systemPropertiesString = "";

distribution/src/bin/elasticsearch-env

@@ -36,23 +36,29 @@ ES_HOME=`dirname "$ES_HOME"`
 ES_CLASSPATH="$ES_HOME/lib/*"
 
 # now set the path to java
-if [ ! -z "$JAVA_HOME" ]; then
+if [ ! -z "$ES_JAVA_HOME" ]; then
+  JAVA="$ES_JAVA_HOME/bin/java"
+  JAVA_TYPE="ES_JAVA_HOME"
+elif [ ! -z "$JAVA_HOME" ]; then
+  # fallback to JAVA_HOME
+  echo "warning: usage of JAVA_HOME is deprecated, use ES_JAVA_HOME" >&2
   JAVA="$JAVA_HOME/bin/java"
   JAVA_TYPE="JAVA_HOME"
 else
+  # use the bundled JDK (default)
   if [ "$(uname -s)" = "Darwin" ]; then
     # macOS has a different structure
     JAVA="$ES_HOME/jdk.app/Contents/Home/bin/java"
   else
     JAVA="$ES_HOME/jdk/bin/java"
   fi
-  JAVA_TYPE="bundled jdk"
+  JAVA_TYPE="bundled JDK"
 fi
 
 if [ ! -x "$JAVA" ]; then
-    echo "could not find java in $JAVA_TYPE at $JAVA" >&2
-    exit 1
-  fi
+  echo "could not find java in $JAVA_TYPE at $JAVA" >&2
+  exit 1
+fi
 
 # do not let JAVA_TOOL_OPTIONS slip in (as the JVM does by default)
 if [ ! -z "$JAVA_TOOL_OPTIONS" ]; then

distribution/src/bin/elasticsearch-env.bat

@@ -40,16 +40,23 @@ if "%1" == "nojava" (
    exit /b
 )
 
-rem compariing to empty string makes this equivalent to bash -v check on env var
+rem comparing to empty string makes this equivalent to bash -v check on env var
 rem and allows to effectively force use of the bundled jdk when launching ES
 rem by setting JAVA_HOME=
-if "%JAVA_HOME%" == "" (
-  set JAVA="%ES_HOME%\jdk\bin\java.exe"
-  set "JAVA_HOME=%ES_HOME%\jdk"
-  set JAVA_TYPE=bundled jdk
-) else (
+if defined ES_JAVA_HOME (
+  set JAVA="%ES_JAVA_HOME%\bin\java.exe"
+  set JAVA_TYPE=ES_JAVA_HOME
+) else if defined JAVA_HOME (
+  rem fallback to JAVA_HOME
+  echo "warning: usage of JAVA_HOME is deprecated, use ES_JAVA_HOME" >&2
   set JAVA="%JAVA_HOME%\bin\java.exe"
+  set "ES_JAVA_HOME=%JAVA_HOME%"
   set JAVA_TYPE=JAVA_HOME
+) else (
+  rem use the bundled JDK (default)
+  set JAVA="%ES_HOME%\jdk\bin\java.exe"
+  set "ES_JAVA_HOME=%ES_HOME%\jdk"
+  set JAVA_TYPE=bundled JDK
 )
 
 if not exist !JAVA! (

distribution/src/bin/elasticsearch-service.bat

@@ -88,20 +88,20 @@ goto:eof
 
 :doInstall
 echo Installing service      :  "%SERVICE_ID%"
-echo Using JAVA_HOME (%ARCH%):  "%JAVA_HOME%"
+echo Using ES_JAVA_HOME (%ARCH%):  "%ES_JAVA_HOME%"
 
 rem Check JVM server dll first
-if exist "%JAVA_HOME%\jre\bin\server\jvm.dll" (
+if exist "%ES_JAVA_HOME%\jre\bin\server\jvm.dll" (
 	set JVM_DLL=\jre\bin\server\jvm.dll
 	goto foundJVM
 )
 
 rem Check 'server' JRE (JRE installed on Windows Server)
-if exist "%JAVA_HOME%\bin\server\jvm.dll" (
+if exist "%ES_JAVA_HOME%\bin\server\jvm.dll" (
 	set JVM_DLL=\bin\server\jvm.dll
 	goto foundJVM
 ) else (
-  	echo JAVA_HOME ("%JAVA_HOME%"^) points to an invalid Java installation (no jvm.dll found in "%JAVA_HOME%\jre\bin\server" or "%JAVA_HOME%\bin\server"^). Exiting...
+  	echo ES_JAVA_HOME ("%ES_JAVA_HOME%"^) points to an invalid Java installation (no jvm.dll found in "%ES_JAVA_HOME%\jre\bin\server" or "%ES_JAVA_HOME%\bin\server"^). Exiting...
   	goto:eof
 )
 
@@ -207,7 +207,7 @@ if not "%SERVICE_USERNAME%" == "" (
 		set SERVICE_PARAMS=%SERVICE_PARAMS% --ServiceUser "%SERVICE_USERNAME%" --ServicePassword "%SERVICE_PASSWORD%"
 	)
 )
-"%EXECUTABLE%" //IS//%SERVICE_ID% --Startup %ES_START_TYPE% --StopTimeout %ES_STOP_TIMEOUT% --StartClass org.elasticsearch.bootstrap.Elasticsearch --StartMethod main ++StartParams --quiet --StopClass org.elasticsearch.bootstrap.Elasticsearch --StopMethod close --Classpath "%ES_CLASSPATH%" --JvmMs %JVM_MS% --JvmMx %JVM_MX% --JvmSs %JVM_SS% --JvmOptions %OTHER_JAVA_OPTS% ++JvmOptions %ES_PARAMS% %LOG_OPTS% --PidFile "%SERVICE_ID%.pid" --DisplayName "%SERVICE_DISPLAY_NAME%" --Description "%SERVICE_DESCRIPTION%" --Jvm "%JAVA_HOME%%JVM_DLL%" --StartMode jvm --StopMode jvm --StartPath "%ES_HOME%" %SERVICE_PARAMS% ++Environment HOSTNAME="%%COMPUTERNAME%%"
+"%EXECUTABLE%" //IS//%SERVICE_ID% --Startup %ES_START_TYPE% --StopTimeout %ES_STOP_TIMEOUT% --StartClass org.elasticsearch.bootstrap.Elasticsearch --StartMethod main ++StartParams --quiet --StopClass org.elasticsearch.bootstrap.Elasticsearch --StopMethod close --Classpath "%ES_CLASSPATH%" --JvmMs %JVM_MS% --JvmMx %JVM_MX% --JvmSs %JVM_SS% --JvmOptions %OTHER_JAVA_OPTS% ++JvmOptions %ES_PARAMS% %LOG_OPTS% --PidFile "%SERVICE_ID%.pid" --DisplayName "%SERVICE_DISPLAY_NAME%" --Description "%SERVICE_DESCRIPTION%" --Jvm "%ES_JAVA_HOME%%JVM_DLL%" --StartMode jvm --StopMode jvm --StartPath "%ES_HOME%" %SERVICE_PARAMS% ++Environment HOSTNAME="%%COMPUTERNAME%%"
 
 if not errorlevel 1 goto installed
 echo Failed installing '%SERVICE_ID%' service
@@ -219,7 +219,7 @@ echo The service '%SERVICE_ID%' has been installed.
 goto:eof
 
 :err
-echo JAVA_HOME environment variable must be set!
+echo ES_JAVA_HOME environment variable must be set!
 pause
 goto:eof
 

docs/reference/setup.asciidoc

@@ -28,7 +28,7 @@ https://openjdk.java.net[OpenJDK] from the JDK maintainers (GPLv2+CE)
 within each distribution. The bundled JVM is the recommended JVM and
 is located within the `jdk` directory of the Elasticsearch home directory.
 
-To use your own version of Java, set the `JAVA_HOME` environment variable.
+To use your own version of Java, set the `ES_JAVA_HOME` environment variable.
 If you must use a version of Java that is different from the bundled JVM,
 we recommend using a link:/support/matrix[supported]
 https://www.oracle.com/technetwork/java/eol-135779.html[LTS version of Java].

docs/reference/setup/install/deb.asciidoc

@@ -198,7 +198,7 @@ locations for a Debian-based system:
 
 | jdk
   | The bundled Java Development Kit used to run Elasticsearch. Can
-    be overridden by setting the `JAVA_HOME` environment variable
+    be overridden by setting the `ES_JAVA_HOME` environment variable
     in `/etc/default/elasticsearch`.
   | /usr/share/elasticsearch/jdk
  d|

docs/reference/setup/install/rpm.asciidoc

@@ -191,7 +191,7 @@ locations for an RPM-based system:
 
 | jdk
   | The bundled Java Development Kit used to run Elasticsearch. Can
-    be overridden by setting the `JAVA_HOME` environment variable
+    be overridden by setting the `ES_JAVA_HOME` environment variable
     in `/etc/sysconfig/elasticsearch`.
   | /usr/share/elasticsearch/jdk
  d|

docs/reference/setup/install/sysconfig-file.asciidoc

@@ -1,5 +1,5 @@
 [horizontal]
-`JAVA_HOME`::
+`ES_JAVA_HOME`::
 
   Set a custom Java path to be used.
 

docs/reference/setup/install/zip-windows.asciidoc

@@ -120,24 +120,24 @@ The commands available are:
 
 `manager`:: Start a GUI for managing the installed service
 
-The name of the service and the value of `JAVA_HOME` will be made available during install:
+The name of the service and the value of `ES_JAVA_HOME` will be made available during install:
 
 ["source","sh",subs="attributes"]
 --------------------------------------------------
 c:\elasticsearch-{version}{backslash}bin>elasticsearch-service.bat install
 Installing service      :  "elasticsearch-service-x64"
-Using JAVA_HOME (64-bit):  "c:\jvm\jdk1.8"
+Using ES_JAVA_HOME (64-bit):  "c:\jvm\jdk1.8"
 The service 'elasticsearch-service-x64' has been installed.
 --------------------------------------------------
 
 NOTE: While a JRE can be used for the Elasticsearch service, due to its use of a client VM (as opposed to a server JVM which offers better performance for long-running applications) its usage is discouraged and a warning will be issued.
 
-NOTE: The system environment variable `JAVA_HOME` should be set to the path to
-the JDK installation that you want the service to use. If you upgrade the JDK,
-you are not required to the reinstall the service but you must set the value of
-the system environment variable `JAVA_HOME` to the path to the new JDK
-installation. However, upgrading across JVM types (e.g. JRE versus SE) is not
-supported, and does require the service to be reinstalled.
+NOTE: The system environment variable `ES_JAVA_HOME` should be set to the path
+to the JDK installation that you want the service to use. If you upgrade the
+JDK, you are not required to the reinstall the service but you must set the
+value of the system environment variable `ES_JAVA_HOME` to the path to the new
+JDK installation. However, upgrading across JVM types (e.g. JRE versus SE) is
+not supported, and does require the service to be reinstalled.
 
 [[windows-service-settings]]
 [discrete]
@@ -167,7 +167,7 @@ The Elasticsearch service can be configured prior to installation by setting the
 
   The description of the service.  Defaults to `Elasticsearch <version> Windows Service - https://elastic.co`.
 
-`JAVA_HOME`::
+`ES_JAVA_HOME`::
 
   The installation directory of the desired JVM to run the service under.
 

modules/reindex/build.gradle

@@ -137,6 +137,7 @@ if (Os.isFamily(Os.FAMILY_WINDOWS)) {
       dependsOn unzip
       executable = "${BuildParams.runtimeJavaHome}/bin/java"
       env 'CLASSPATH', "${-> project.configurations.oldesFixture.asPath}"
+      // old versions of Elasticsearch need JAVA_HOME
       env 'JAVA_HOME', jdks.legacy.javaHomePath
       args 'oldes.OldElasticsearch',
         baseDir,

qa/os/src/test/java/org/elasticsearch/packaging/test/ArchiveTests.java

@@ -62,7 +62,7 @@ public class ArchiveTests extends PackagingTestCase {
 
     public void test30MissingBundledJdk() throws Exception {
         final Installation.Executables bin = installation.executables();
-        sh.getEnv().remove("JAVA_HOME");
+        sh.getEnv().remove("ES_JAVA_HOME");
 
         final Path relocatedJdk = installation.bundledJdk.getParent().resolve("jdk.relocated");
 
@@ -73,7 +73,7 @@ public class ArchiveTests extends PackagingTestCase {
             // ask for elasticsearch version to quickly exit if java is actually found (ie test failure)
             final Result runResult = sh.runIgnoreExitCode(bin.elasticsearch.toString() + " -v");
             assertThat(runResult.exitCode, is(1));
-            assertThat(runResult.stderr, containsString("could not find java in bundled jdk"));
+            assertThat(runResult.stderr, containsString("could not find java in bundled JDK"));
         } finally {
             if (distribution().hasJdk) {
                 mv(relocatedJdk, installation.bundledJdk);
@@ -83,13 +83,12 @@ public class ArchiveTests extends PackagingTestCase {
 
     public void test31BadJavaHome() throws Exception {
         final Installation.Executables bin = installation.executables();
-        sh.getEnv().put("JAVA_HOME", "doesnotexist");
+        sh.getEnv().put("ES_JAVA_HOME", "doesnotexist");
 
         // ask for elasticsearch version to quickly exit if java is actually found (ie test failure)
         final Result runResult = sh.runIgnoreExitCode(bin.elasticsearch.toString() + " -V");
         assertThat(runResult.exitCode, is(1));
-        assertThat(runResult.stderr, containsString("could not find java in JAVA_HOME"));
-
+        assertThat(runResult.stderr, containsString("could not find java in ES_JAVA_HOME"));
     }
 
     public void test32SpecialCharactersInJdkPath() throws Exception {
@@ -97,7 +96,7 @@ public class ArchiveTests extends PackagingTestCase {
         assumeTrue("Only run this test when we know where the JDK is.", distribution().hasJdk);
 
         final Path relocatedJdk = installation.bundledJdk.getParent().resolve("a (special) path");
-        sh.getEnv().put("JAVA_HOME", relocatedJdk.toString());
+        sh.getEnv().put("ES_JAVA_HOME", relocatedJdk.toString());
 
         try {
             mv(installation.bundledJdk, relocatedJdk);
@@ -130,16 +129,42 @@ public class ArchiveTests extends PackagingTestCase {
         stopElasticsearch();
     }
 
+    public void test51EsJavaHomeOverride() throws Exception {
+        Platforms.onLinux(() -> {
+            String systemJavaHome1 = sh.run("echo $SYSTEM_JAVA_HOME").stdout.trim();
+            sh.getEnv().put("ES_JAVA_HOME", systemJavaHome1);
+        });
+        Platforms.onWindows(() -> {
+            final String systemJavaHome1 = sh.run("$Env:SYSTEM_JAVA_HOME").stdout.trim();
+            sh.getEnv().put("ES_JAVA_HOME", systemJavaHome1);
+        });
+
+        startElasticsearch();
+        ServerUtils.runElasticsearchTests();
+        stopElasticsearch();
+
+        String systemJavaHome1 = sh.getEnv().get("ES_JAVA_HOME");
+        assertThat(FileUtils.slurpAllLogs(installation.logs, "elasticsearch.log", "*.log.gz"), containsString(systemJavaHome1));
+    }
+
     public void test51JavaHomeOverride() throws Exception {
         Platforms.onLinux(() -> {
             String systemJavaHome1 = sh.run("echo $SYSTEM_JAVA_HOME").stdout.trim();
             sh.getEnv().put("JAVA_HOME", systemJavaHome1);
+            // ensure that ES_JAVA_HOME is not set for the test
+            sh.getEnv().remove("ES_JAVA_HOME");
         });
         Platforms.onWindows(() -> {
             final String systemJavaHome1 = sh.run("$Env:SYSTEM_JAVA_HOME").stdout.trim();
             sh.getEnv().put("JAVA_HOME", systemJavaHome1);
+            // ensure that ES_JAVA_HOME is not set for the test
+            sh.getEnv().remove("ES_JAVA_HOME");
         });
 
+        final Installation.Executables bin = installation.executables();
+        final Result runResult = sh.run(bin.elasticsearch.toString() + " -V");
+        assertThat(runResult.stderr, containsString("warning: usage of JAVA_HOME is deprecated, use ES_JAVA_HOME"));
+
         startElasticsearch();
         ServerUtils.runElasticsearchTests();
         stopElasticsearch();
@@ -148,6 +173,32 @@ public class ArchiveTests extends PackagingTestCase {
         assertThat(FileUtils.slurpAllLogs(installation.logs, "elasticsearch.log", "*.log.gz"), containsString(systemJavaHome1));
     }
 
+    public void test51EsJavaHomeOverrideOverridesJavaHome() throws Exception {
+        Platforms.onLinux(() -> {
+            String systemJavaHome1 = sh.run("echo $SYSTEM_JAVA_HOME").stdout.trim();
+            sh.getEnv().put("ES_JAVA_HOME", systemJavaHome1);
+            // deliberately set to a location that does not exist, if ES_JAVA_HOME takes precedence this is ignored
+            sh.getEnv().put("JAVA_HOME", "doesnotexist");
+        });
+        Platforms.onWindows(() -> {
+            final String systemJavaHome1 = sh.run("$Env:SYSTEM_JAVA_HOME").stdout.trim();
+            sh.getEnv().put("ES_JAVA_HOME", systemJavaHome1);
+            // deliberately set to a location that does not exist, if ES_JAVA_HOME takes precedence this is ignored
+            sh.getEnv().put("JAVA_HOME", "doesnotexist");
+        });
+
+        final Installation.Executables bin = installation.executables();
+        final Result runResult = sh.run(bin.elasticsearch.toString() + " -V");
+        assertThat(runResult.stderr, not(containsString("warning: usage of JAVA_HOME is deprecated, use ES_JAVA_HOME")));
+
+        startElasticsearch();
+        ServerUtils.runElasticsearchTests();
+        stopElasticsearch();
+
+        String systemJavaHome1 = sh.getEnv().get("ES_JAVA_HOME");
+        assertThat(FileUtils.slurpAllLogs(installation.logs, "elasticsearch.log", "*.log.gz"), containsString(systemJavaHome1));
+    }
+
     public void test52BundledJdkRemoved() throws Exception {
         assumeThat(distribution().hasJdk, is(true));
 
@@ -156,18 +207,18 @@ public class ArchiveTests extends PackagingTestCase {
             mv(installation.bundledJdk, relocatedJdk);
             Platforms.onLinux(() -> {
                 String systemJavaHome1 = sh.run("echo $SYSTEM_JAVA_HOME").stdout.trim();
-                sh.getEnv().put("JAVA_HOME", systemJavaHome1);
+                sh.getEnv().put("ES_JAVA_HOME", systemJavaHome1);
             });
             Platforms.onWindows(() -> {
                 final String systemJavaHome1 = sh.run("$Env:SYSTEM_JAVA_HOME").stdout.trim();
-                sh.getEnv().put("JAVA_HOME", systemJavaHome1);
+                sh.getEnv().put("ES_JAVA_HOME", systemJavaHome1);
             });
 
             startElasticsearch();
             ServerUtils.runElasticsearchTests();
             stopElasticsearch();
 
-            String systemJavaHome1 = sh.getEnv().get("JAVA_HOME");
+            String systemJavaHome1 = sh.getEnv().get("ES_JAVA_HOME");
             assertThat(FileUtils.slurpAllLogs(installation.logs, "elasticsearch.log", "*.log.gz"), containsString(systemJavaHome1));
         } finally {
             mv(relocatedJdk, installation.bundledJdk);
@@ -181,7 +232,7 @@ public class ArchiveTests extends PackagingTestCase {
                 // once windows 2012 is no longer supported and powershell 5.0 is always available we can change this command
                 sh.run("cmd /c mklink /D '" + javaPath + "' $Env:SYSTEM_JAVA_HOME");
 
-                sh.getEnv().put("JAVA_HOME", "C:\\Program Files (x86)\\java");
+                sh.getEnv().put("ES_JAVA_HOME", "C:\\Program Files (x86)\\java");
 
                 // verify ES can start, stop and run plugin list
                 startElasticsearch();
@@ -206,7 +257,7 @@ public class ArchiveTests extends PackagingTestCase {
             try {
                 final String systemJavaHome = sh.run("echo $SYSTEM_JAVA_HOME").stdout.trim();
                 sh.run("ln -s \"" + systemJavaHome + "\" \"" + testJavaHome + "\"");
-                sh.getEnv().put("JAVA_HOME", testJavaHome);
+                sh.getEnv().put("ES_JAVA_HOME", testJavaHome);
 
                 // verify ES can start, stop and run plugin list
                 startElasticsearch();
@@ -227,7 +278,7 @@ public class ArchiveTests extends PackagingTestCase {
         // cleanup from previous test
         rm(installation.config("elasticsearch.keystore"));
 
-        sh.getEnv().put("JAVA_HOME", "");
+        sh.getEnv().put("ES_JAVA_HOME", "");
 
         startElasticsearch();
         ServerUtils.runElasticsearchTests();

qa/os/src/test/java/org/elasticsearch/packaging/test/PackageTests.java

@@ -83,7 +83,7 @@ public class PackageTests extends PackagingTestCase {
     private void assertRunsWithJavaHome() throws Exception {
         byte[] originalEnvFile = Files.readAllBytes(installation.envFile);
         try {
-            Files.write(installation.envFile, List.of("JAVA_HOME=" + systemJavaHome), APPEND);
+            Files.write(installation.envFile, List.of("ES_JAVA_HOME=" + systemJavaHome), APPEND);
             startElasticsearch();
             runElasticsearchTests();
             stopElasticsearch();

qa/os/src/test/java/org/elasticsearch/packaging/test/PackagingTestCase.java

@@ -161,8 +161,8 @@ public abstract class PackagingTestCase extends Assert {
 
         sh.reset();
         if (distribution().hasJdk == false) {
-            Platforms.onLinux(() -> sh.getEnv().put("JAVA_HOME", systemJavaHome));
-            Platforms.onWindows(() -> sh.getEnv().put("JAVA_HOME", systemJavaHome));
+            Platforms.onLinux(() -> sh.getEnv().put("ES_JAVA_HOME", systemJavaHome));
+            Platforms.onWindows(() -> sh.getEnv().put("ES_JAVA_HOME", systemJavaHome));
         }
         if (installation != null && distribution.isDocker() == false) {
             setHeap("1g");

qa/os/src/test/java/org/elasticsearch/packaging/test/WindowsServiceTests.java

@@ -118,17 +118,17 @@ public class WindowsServiceTests extends PackagingTestCase {
             mv(installation.bundledJdk, relocatedJdk);
             Result result = sh.runIgnoreExitCode(serviceScript + " install");
             assertThat(result.exitCode, equalTo(1));
-            assertThat(result.stderr, containsString("could not find java in bundled jdk"));
+            assertThat(result.stderr, containsString("could not find java in bundled JDK"));
         } finally {
             mv(relocatedJdk, installation.bundledJdk);
         }
     }
 
     public void test14InstallBadJavaHome() throws IOException {
-        sh.getEnv().put("JAVA_HOME", "doesnotexist");
+        sh.getEnv().put("ES_JAVA_HOME", "doesnotexist");
         Result result = sh.runIgnoreExitCode(serviceScript + " install");
         assertThat(result.exitCode, equalTo(1));
-        assertThat(result.stderr, containsString("could not find java in JAVA_HOME"));
+        assertThat(result.stderr, containsString("could not find java in ES_JAVA_HOME"));
     }
 
     public void test15RemoveNotInstalled() {
@@ -139,7 +139,7 @@ public class WindowsServiceTests extends PackagingTestCase {
     public void test16InstallSpecialCharactersInJdkPath() throws IOException {
         assumeTrue("Only run this test when we know where the JDK is.", distribution().hasJdk);
         final Path relocatedJdk = installation.bundledJdk.getParent().resolve("a (special) jdk");
-        sh.getEnv().put("JAVA_HOME", relocatedJdk.toString());
+        sh.getEnv().put("ES_JAVA_HOME", relocatedJdk.toString());
 
         try {
             mv(installation.bundledJdk, relocatedJdk);
@@ -227,9 +227,9 @@ public class WindowsServiceTests extends PackagingTestCase {
 
         try {
             mv(installation.bundledJdk, relocatedJdk);
-            sh.getEnv().put("JAVA_HOME", relocatedJdk.toString());
+            sh.getEnv().put("ES_JAVA_HOME", relocatedJdk.toString());
             assertCommand(serviceScript + " install");
-            sh.getEnv().remove("JAVA_HOME");
+            sh.getEnv().remove("ES_JAVA_HOME");
             assertCommand(serviceScript + " start");
             assertStartedAndStop();
         } finally {

qa/os/src/test/java/org/elasticsearch/packaging/util/Packages.java

@@ -77,7 +77,7 @@ public class Packages {
     public static Installation installPackage(Shell sh, Distribution distribution) throws IOException {
         String systemJavaHome = sh.run("echo $SYSTEM_JAVA_HOME").stdout.trim();
         if (distribution.hasJdk == false) {
-            sh.getEnv().put("JAVA_HOME", systemJavaHome);
+            sh.getEnv().put("ES_JAVA_HOME", systemJavaHome);
         }
         final Result result = runPackageManager(distribution, sh, PackageManagerCommand.INSTALL);
         if (result.exitCode != 0) {
@@ -87,7 +87,7 @@ public class Packages {
         Installation installation = Installation.ofPackage(sh, distribution);
 
         if (distribution.hasJdk == false) {
-            Files.write(installation.envFile, List.of("JAVA_HOME=" + systemJavaHome), StandardOpenOption.APPEND);
+            Files.write(installation.envFile, List.of("ES_JAVA_HOME=" + systemJavaHome), StandardOpenOption.APPEND);
         }
         return installation;
     }

qa/os/src/test/java/org/elasticsearch/packaging/util/Shell.java

@@ -155,7 +155,8 @@ public class Shell {
         if (workingDirectory != null) {
             setWorkingDirectory(builder, workingDirectory);
         }
-        builder.environment().keySet().remove("JAVA_HOME"); // start with a fresh environment
+        builder.environment().keySet().remove("ES_JAVA_HOME"); // start with a fresh environment
+        builder.environment().keySet().remove("JAVA_HOME");
         for (Map.Entry<String, String> entry : env.entrySet()) {
             builder.environment().put(entry.getKey(), entry.getValue());
         }

x-pack/docs/en/security/fips-140-compliance.asciidoc

@@ -153,8 +153,8 @@ features are not available while running in FIPS 140-2 mode. The list is as foll
 * Ingest Attachment Plugin
 * The <<certutil,`elasticsearch-certutil`>> tool. However,
  `elasticsearch-certutil` can very well be used in a non FIPS 140-2
-  configured JVM (pointing `JAVA_HOME` environment variable to a different java
-  installation) in order to generate the keys and certificates that
+  configured JVM (pointing `ES_JAVA_HOME` environment variable to a different
+  java installation) in order to generate the keys and certificates that
   can be later used in the FIPS 140-2 configured JVM.
 * The SQL CLI client cannot run in a FIPS 140-2 configured JVM while using
   TLS for transport security or PKI for client authentication.