YARN-2803. MR distributed cache not working correctly on Windows after NodeManager privileged account changes. Contributed by Craig Welch.

(cherry picked from commit 06b797947c980d7d21864eb8b700cf565756aac1)
(cherry picked from commit c16f7182937dc4e8bbf46dfedd9db427a0a33357)

hadoop-yarn-project/CHANGES.txt

@@ -828,6 +828,9 @@ Release 2.6.0 - UNRELEASED
 
     YARN-2827. Fixed bugs in "yarn queue" CLI. (Wangda Tan via vinodkv).
 
+    YARN-2803. MR distributed cache not working correctly on Windows after
+    NodeManager privileged account changes. (Craig Welch via cnauroth)
+
 Release 2.5.2 - UNRELEASED
 
   INCOMPATIBLE CHANGES

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-nodemanager/src/main/java/org/apache/hadoop/yarn/server/nodemanager/containermanager/launcher/ContainerLaunch.java

@@ -71,6 +71,7 @@ import org.apache.hadoop.yarn.server.nodemanager.containermanager.container.Cont
 import org.apache.hadoop.yarn.server.nodemanager.containermanager.container.ContainerState;
 import org.apache.hadoop.yarn.server.nodemanager.containermanager.localizer.ContainerLocalizer;
 import org.apache.hadoop.yarn.server.nodemanager.containermanager.localizer.ResourceLocalizationService;
+import org.apache.hadoop.yarn.server.nodemanager.WindowsSecureContainerExecutor;
 import org.apache.hadoop.yarn.server.nodemanager.util.ProcessIdFileReader;
 import org.apache.hadoop.yarn.util.Apps;
 import org.apache.hadoop.yarn.util.AuxiliaryServiceHelper;
@@ -767,8 +768,17 @@ public class ContainerLaunch implements Callable<Integer> {
           System.getenv());
         mergedEnv.putAll(environment);
         
+        // this is hacky and temporary - it's to preserve the windows secure
+        // behavior but enable non-secure windows to properly build the class
+        // path for access to job.jar/lib/xyz and friends (see YARN-2803)
+        Path jarDir;
+        if (exec instanceof WindowsSecureContainerExecutor) {
+          jarDir = nmPrivateClasspathJarDir;
+        } else {
+          jarDir = pwd; 
+        }
         String[] jarCp = FileUtil.createJarWithClassPath(
-          newClassPath.toString(), nmPrivateClasspathJarDir, pwd, mergedEnv);
+          newClassPath.toString(), jarDir, pwd, mergedEnv);
         // In a secure cluster the classpath jar must be localized to grant access
         Path localizedClassPathJar = exec.localizeClasspathJar(
             new Path(jarCp[0]), pwd, container.getUser());