diff --git a/hadoop-common-project/hadoop-common/CHANGES.txt b/hadoop-common-project/hadoop-common/CHANGES.txt
index 05eb383738..717bd24978 100644
--- a/hadoop-common-project/hadoop-common/CHANGES.txt
+++ b/hadoop-common-project/hadoop-common/CHANGES.txt
@@ -125,6 +125,8 @@ Trunk (Unreleased)
 
     HADOOP-10485. Remove dead classes in hadoop-streaming. (wheat9)
 
+    HADOOP-11013. CLASSPATH handling should be consolidated, debuggable (aw)
+
   BUG FIXES
 
     HADOOP-9451. Fault single-layer config if node group topology is enabled.
diff --git a/hadoop-common-project/hadoop-common/src/main/bin/hadoop b/hadoop-common-project/hadoop-common/src/main/bin/hadoop
index 24c4d18e82..64c67587dc 100755
--- a/hadoop-common-project/hadoop-common/src/main/bin/hadoop
+++ b/hadoop-common-project/hadoop-common/src/main/bin/hadoop
@@ -114,6 +114,7 @@ case ${COMMAND} in
   ;;
   archive)
     CLASS=org.apache.hadoop.tools.HadoopArchives
+    hadoop_debug "Injecting TOOL_PATH into CLASSPATH"
     hadoop_add_classpath "${TOOL_PATH}"
   ;;
   checknative)
@@ -136,10 +137,12 @@ case ${COMMAND} in
   ;;
   distch)
     CLASS=org.apache.hadoop.tools.DistCh
+    hadoop_debug "Injecting TOOL_PATH into CLASSPATH"
     hadoop_add_classpath "${TOOL_PATH}"
   ;;
   distcp)
     CLASS=org.apache.hadoop.tools.DistCp
+    hadoop_debug "Injecting TOOL_PATH into CLASSPATH"
     hadoop_add_classpath "${TOOL_PATH}"
   ;;
   fs)
@@ -168,11 +171,11 @@ case ${COMMAND} in
 esac
 
 # Always respect HADOOP_OPTS and HADOOP_CLIENT_OPTS
+hadoop_debug "Appending HADOOP_CLIENT_OPTS onto HADOOP_OPTS"
 HADOOP_OPTS="${HADOOP_OPTS} ${HADOOP_CLIENT_OPTS}"
 
 hadoop_add_param HADOOP_OPTS Xmx "${JAVA_HEAP_MAX}"
 
 hadoop_finalize
-export CLASSPATH
 hadoop_java_exec "${COMMAND}" "${CLASS}" "$@"
 
diff --git a/hadoop-common-project/hadoop-common/src/main/bin/hadoop-config.sh b/hadoop-common-project/hadoop-common/src/main/bin/hadoop-config.sh
index 0cf8bcfc78..40494b3ba4 100644
--- a/hadoop-common-project/hadoop-common/src/main/bin/hadoop-config.sh
+++ b/hadoop-common-project/hadoop-common/src/main/bin/hadoop-config.sh
@@ -129,6 +129,11 @@ while [[ -z "${_hadoop_common_done}" ]]; do
         hadoop_exit_with_usage 1
       fi
     ;;
+    --debug)
+      shift
+      # shellcheck disable=SC2034
+      HADOOP_SHELL_SCRIPT_DEBUG=true
+    ;; 
     --help|-help|-h|help|--h|--\?|-\?|\?)
       hadoop_exit_with_usage 0
     ;;
diff --git a/hadoop-common-project/hadoop-common/src/main/bin/hadoop-functions.sh b/hadoop-common-project/hadoop-common/src/main/bin/hadoop-functions.sh
index 800e024485..dd5520cab1 100644
--- a/hadoop-common-project/hadoop-common/src/main/bin/hadoop-functions.sh
+++ b/hadoop-common-project/hadoop-common/src/main/bin/hadoop-functions.sh
@@ -21,6 +21,13 @@ function hadoop_error
   echo "$*" 1>&2
 }
 
+function hadoop_debug
+{
+  if [[ -n "${HADOOP_SHELL_SCRIPT_DEBUG}" ]]; then
+    echo "DEBUG: $*" 1>&2
+  fi
+}
+
 function hadoop_bootstrap_init
 {
   # NOTE: This function is not user replaceable.
@@ -62,6 +69,7 @@ function hadoop_bootstrap_init
  
   # defaults
   export HADOOP_OPTS=${HADOOP_OPTS:-"-Djava.net.preferIPv4Stack=true"}
+  hadoop_debug "Initial HADOOP_OPTS=${HADOOP_OPTS}"
 }
 
 function hadoop_find_confdir
@@ -80,6 +88,8 @@ function hadoop_find_confdir
     conf_dir="etc/hadoop"
   fi
   export HADOOP_CONF_DIR="${HADOOP_CONF_DIR:-${HADOOP_PREFIX}/${conf_dir}}"
+
+  hadoop_debug "HADOOP_CONF_DIR=${HADOOP_CONF_DIR}"
 }
 
 function hadoop_exec_hadoopenv
@@ -105,6 +115,7 @@ function hadoop_basic_init
   
   # CLASSPATH initially contains $HADOOP_CONF_DIR
   CLASSPATH="${HADOOP_CONF_DIR}"
+  hadoop_debug "Initial CLASSPATH=${HADOOP_CONF_DIR}"
   
   if [[ -z "${HADOOP_COMMON_HOME}" ]] &&
   [[ -d "${HADOOP_PREFIX}/${HADOOP_COMMON_DIR}" ]]; then
@@ -116,19 +127,19 @@ function hadoop_basic_init
   
   # define HADOOP_HDFS_HOME
   if [[ -z "${HADOOP_HDFS_HOME}" ]] &&
-  [[ -d "${HADOOP_PREFIX}/${HDFS_DIR}" ]]; then
+     [[ -d "${HADOOP_PREFIX}/${HDFS_DIR}" ]]; then
     export HADOOP_HDFS_HOME="${HADOOP_PREFIX}"
   fi
   
   # define HADOOP_YARN_HOME
   if [[ -z "${HADOOP_YARN_HOME}" ]] &&
-  [[ -d "${HADOOP_PREFIX}/${YARN_DIR}" ]]; then
+     [[ -d "${HADOOP_PREFIX}/${YARN_DIR}" ]]; then
     export HADOOP_YARN_HOME="${HADOOP_PREFIX}"
   fi
   
   # define HADOOP_MAPRED_HOME
   if [[ -z "${HADOOP_MAPRED_HOME}" ]] &&
-  [[ -d "${HADOOP_PREFIX}/${MAPRED_DIR}" ]]; then
+     [[ -d "${HADOOP_PREFIX}/${MAPRED_DIR}" ]]; then
     export HADOOP_MAPRED_HOME="${HADOOP_PREFIX}"
   fi
   
@@ -274,6 +285,9 @@ function hadoop_add_param
   if [[ ! ${!1} =~ $2 ]] ; then
     # shellcheck disable=SC2086
     eval $1="'${!1} $3'"
+    hadoop_debug "$1 accepted $3"
+  else
+    hadoop_debug "$1 declined $3"
   fi
 }
 
@@ -283,8 +297,8 @@ function hadoop_add_classpath
   # $1 = directory, file, wildcard, whatever to add
   # $2 = before or after, which determines where in the
   #      classpath this object should go. default is after
-  # return 0 = success
-  # return 1 = failure (duplicate, doesn't exist, whatever)
+  # return 0 = success (added or duplicate)
+  # return 1 = failure (doesn't exist, whatever)
   
   # However, with classpath (& JLP), we can do dedupe
   # along with some sanity checking (e.g., missing directories)
@@ -295,23 +309,29 @@ function hadoop_add_classpath
   if [[ $1 =~ ^.*\*$ ]]; then
     local mp=$(dirname "$1")
     if [[ ! -d "${mp}" ]]; then
+      hadoop_debug "Rejected CLASSPATH: $1 (not a dir)"
       return 1
     fi
     
     # no wildcard in the middle, so check existence
     # (doesn't matter *what* it is)
   elif [[ ! $1 =~ ^.*\*.*$ ]] && [[ ! -e "$1" ]]; then
+    hadoop_debug "Rejected CLASSPATH: $1 (does not exist)"
     return 1
   fi
-  
   if [[ -z "${CLASSPATH}" ]]; then
     CLASSPATH=$1
+    hadoop_debug "Initial CLASSPATH=$1"
   elif [[ ":${CLASSPATH}:" != *":$1:"* ]]; then
     if [[ "$2" = "before" ]]; then
       CLASSPATH="$1:${CLASSPATH}"
+      hadoop_debug "Prepend CLASSPATH: $1"
     else
       CLASSPATH+=:$1
+      hadoop_debug "Append CLASSPATH: $1"
     fi
+  else
+    hadoop_debug "Dupe CLASSPATH: $1"
   fi
   return 0
 }
@@ -331,14 +351,20 @@ function hadoop_add_colonpath
     if [[ -z "${!1}" ]]; then
       # shellcheck disable=SC2086
       eval $1="'$2'"
+      hadoop_debug "Initial colonpath($1): $2"
     elif [[ "$3" = "before" ]]; then
       # shellcheck disable=SC2086
       eval $1="'$2:${!1}'"
+      hadoop_debug "Prepend colonpath($1): $2"
     else
       # shellcheck disable=SC2086
       eval $1+="'$2'"
+      hadoop_debug "Append colonpath($1): $2"
     fi
+    return 0
   fi
+  hadoop_debug "Rejected colonpath($1): $2"
+  return 1
 }
 
 function hadoop_add_javalibpath
@@ -397,6 +423,7 @@ function hadoop_add_to_classpath_hdfs
 
 function hadoop_add_to_classpath_yarn
 {
+  local i
   #
   # get all of the yarn jars+config in the path
   #
@@ -459,7 +486,7 @@ function hadoop_add_to_classpath_userpath
   local i
   local j
   let c=0
-  
+
   if [[ -n "${HADOOP_CLASSPATH}" ]]; then
     # I wonder if Java runs on VMS.
     for i in $(echo "${HADOOP_CLASSPATH}" | tr : '\n'); do
@@ -715,6 +742,11 @@ function hadoop_java_exec
   local command=$1
   local class=$2
   shift 2
+  
+  hadoop_debug "Final CLASSPATH: ${CLASSPATH}"
+  hadoop_debug "Final HADOOP_OPTS: ${HADOOP_OPTS}"
+
+  export CLASSPATH
   #shellcheck disable=SC2086
   exec "${JAVA}" "-Dproc_${command}" ${HADOOP_OPTS} "${class}" "$@"
 }
@@ -727,6 +759,11 @@ function hadoop_start_daemon
   local command=$1
   local class=$2
   shift 2
+
+  hadoop_debug "Final CLASSPATH: ${CLASSPATH}"
+  hadoop_debug "Final HADOOP_OPTS: ${HADOOP_OPTS}"
+
+  export CLASSPATH
   #shellcheck disable=SC2086
   exec "${JAVA}" "-Dproc_${command}" ${HADOOP_OPTS} "${class}" "$@"
 }
@@ -807,6 +844,9 @@ function hadoop_start_secure_daemon
   # note that shellcheck will throw a
   # bogus for-our-use-case 2086 here.
   # it doesn't properly support multi-line situations
+
+  hadoop_debug "Final CLASSPATH: ${CLASSPATH}"
+  hadoop_debug "Final HADOOP_OPTS: ${HADOOP_OPTS}"
   
   exec "${jsvc}" \
   "-Dproc_${daemonname}" \
diff --git a/hadoop-common-project/hadoop-common/src/main/bin/rcc b/hadoop-common-project/hadoop-common/src/main/bin/rcc
index dc6158a8ea..74253539fb 100755
--- a/hadoop-common-project/hadoop-common/src/main/bin/rcc
+++ b/hadoop-common-project/hadoop-common/src/main/bin/rcc
@@ -23,6 +23,7 @@ this="$bin/$script"
 
 DEFAULT_LIBEXEC_DIR="$bin"/../libexec
 HADOOP_LIBEXEC_DIR=${HADOOP_LIBEXEC_DIR:-$DEFAULT_LIBEXEC_DIR}
+# shellcheck disable=SC2034
 HADOOP_NEW_CONFIG=true
 . "$HADOOP_LIBEXEC_DIR/hadoop-config.sh"
 
@@ -33,10 +34,10 @@ fi
 CLASS='org.apache.hadoop.record.compiler.generated.Rcc'
 
 # Always respect HADOOP_OPTS and HADOOP_CLIENT_OPTS
-HADOOP_OPTS="$HADOOP_OPTS $HADOOP_CLIENT_OPTS"
+hadoop_debug "Appending HADOOP_CLIENT_OPTS onto HADOOP_OPTS"
+HADOOP_OPTS="${HADOOP_OPTS} ${HADOOP_CLIENT_OPTS}"
 
-hadoop_add_param HADOOP_OPTS Xmx "$JAVA_HEAP_MAX"
+hadoop_add_param HADOOP_OPTS Xmx "${JAVA_HEAP_MAX}"
 
 hadoop_finalize
-export CLASSPATH
 hadoop_java_exec rcc "${CLASS}" "$@"
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/bin/hdfs b/hadoop-hdfs-project/hadoop-hdfs/src/main/bin/hdfs
index 77f1582db2..6872a0eb1a 100755
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/bin/hdfs
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/bin/hdfs
@@ -80,6 +80,7 @@ shift
 case ${COMMAND} in
   balancer)
     CLASS=org.apache.hadoop.hdfs.server.balancer.Balancer
+    hadoop_debug "Appending HADOOP_BALANCER_OPTS onto HADOOP_OPTS"
     HADOOP_OPTS="${HADOOP_OPTS} ${HADOOP_BALANCER_OPTS}"
   ;;
   cacheadmin)
@@ -105,19 +106,24 @@ case ${COMMAND} in
       HADOOP_SECURE_PID_DIR="${HADOOP_SECURE_PID_DIR:-$HADOOP_SECURE_DN_PID_DIR}"
       HADOOP_SECURE_LOG_DIR="${HADOOP_SECURE_LOG_DIR:-$HADOOP_SECURE_DN_LOG_DIR}"
       
-      HADOOP_OPTS="${HADOOP_OPTS} ${HADOOP_DN_SECURE_EXTRA_OPTS} ${HADOOP_DATANODE_OPTS}"
+      hadoop_debug "Appending HADOOP_DATANODE_OPTS onto HADOOP_OPTS"
+      hadoop_debug "Appending HADOOP_DN_SECURE_EXTRA_OPTS onto HADOOP_OPTS"
+      HADOOP_OPTS="${HADOOP_OPTS} ${HADOOP_DATANODE_OPTS} ${HADOOP_DN_SECURE_EXTRA_OPTS}"
       CLASS="org.apache.hadoop.hdfs.server.datanode.SecureDataNodeStarter"
     else
+      hadoop_debug "Appending HADOOP_DATANODE_OPTS onto HADOOP_OPTS"
       HADOOP_OPTS="${HADOOP_OPTS} ${HADOOP_DATANODE_OPTS}"
       CLASS='org.apache.hadoop.hdfs.server.datanode.DataNode'
     fi
   ;;
   dfs)
     CLASS=org.apache.hadoop.fs.FsShell
+    hadoop_debug "Appending HADOOP_CLIENT_OPTS onto HADOOP_OPTS"
     HADOOP_OPTS="${HADOOP_OPTS} ${HADOOP_CLIENT_OPTS}"
   ;;
   dfsadmin)
     CLASS=org.apache.hadoop.hdfs.tools.DFSAdmin
+    hadoop_debug "Appending HADOOP_CLIENT_OPTS onto HADOOP_OPTS"
     HADOOP_OPTS="${HADOOP_OPTS} ${HADOOP_CLIENT_OPTS}"
   ;;
   fetchdt)
@@ -125,6 +131,7 @@ case ${COMMAND} in
   ;;
   fsck)
     CLASS=org.apache.hadoop.hdfs.tools.DFSck
+    hadoop_debug "Appending HADOOP_CLIENT_OPTS onto HADOOP_OPTS"
     HADOOP_OPTS="${HADOOP_OPTS} ${HADOOP_CLIENT_OPTS}"
   ;;
   getconf)
@@ -135,12 +142,15 @@ case ${COMMAND} in
   ;;
   haadmin)
     CLASS=org.apache.hadoop.hdfs.tools.DFSHAAdmin
-    CLASSPATH="${CLASSPATH}:${TOOL_PATH}"
+    hadoop_debug "Injecting TOOL_PATH into CLASSPATH"
+    hadoop_add_classpath "${TOOL_PATH}"
+    hadoop_debug "Appending HADOOP_CLIENT_OPTS onto HADOOP_OPTS"
     HADOOP_OPTS="${HADOOP_OPTS} ${HADOOP_CLIENT_OPTS}"
   ;;
   journalnode)
     daemon="true"
     CLASS='org.apache.hadoop.hdfs.qjournal.server.JournalNode'
+    hadoop_debug "Appending HADOOP_JOURNALNODE_OPTS onto HADOOP_OPTS"
     HADOOP_OPTS="${HADOOP_OPTS} ${HADOOP_JOURNALNODE_OPTS}"
   ;;
   jmxget)
@@ -152,6 +162,7 @@ case ${COMMAND} in
   namenode)
     daemon="true"
     CLASS='org.apache.hadoop.hdfs.server.namenode.NameNode'
+    hadoop_debug "Appending HADOOP_NAMENODE_OPTS onto HADOOP_OPTS"
     HADOOP_OPTS="${HADOOP_OPTS} ${HADOOP_NAMENODE_OPTS}"
   ;;
   nfs3)
@@ -164,9 +175,12 @@ case ${COMMAND} in
       HADOOP_SECURE_PID_DIR="${HADOOP_SECURE_PID_DIR:-$HADOOP_SECURE_NFS3_PID_DIR}"
       HADOOP_SECURE_LOG_DIR="${HADOOP_SECURE_LOG_DIR:-$HADOOP_SECURE_NFS3_LOG_DIR}"
       
-      HADOOP_OPTS="${HADOOP_OPTS} ${HADOOP_NFS3_SECURE_EXTRA_OPTS} ${HADOOP_NFS3_OPTS}"
+      hadoop_debug "Appending HADOOP_NFS3_OPTS onto HADOOP_OPTS"
+      hadoop_debug "Appending HADOOP_NFS3_SECURE_EXTRA_OPTS onto HADOOP_OPTS"
+      HADOOP_OPTS="${HADOOP_OPTS} ${HADOOP_NFS3_OPTS} ${HADOOP_NFS3_SECURE_EXTRA_OPTS}"
       CLASS=org.apache.hadoop.hdfs.nfs.nfs3.PrivilegedNfsGatewayStarter
     else
+      hadoop_debug "Appending HADOOP_NFS3_OPTS onto HADOOP_OPTS"
       HADOOP_OPTS="${HADOOP_OPTS} ${HADOOP_NFS3_OPTS}"
       CLASS=org.apache.hadoop.hdfs.nfs.nfs3.Nfs3
     fi
@@ -183,11 +197,13 @@ case ${COMMAND} in
   portmap)
     daemon="true"
     CLASS=org.apache.hadoop.portmap.Portmap
+    hadoop_debug "Appending HADOOP_PORTMAP_OPTS onto HADOOP_OPTS"
     HADOOP_OPTS="${HADOOP_OPTS} ${HADOOP_PORTMAP_OPTS}"
   ;;
   secondarynamenode)
     daemon="true"
     CLASS='org.apache.hadoop.hdfs.server.namenode.SecondaryNameNode'
+    hadoop_debug "Appending HADOOP_SECONDARYNAMENODE_OPTS onto HADOOP_OPTS"
     HADOOP_OPTS="${HADOOP_OPTS} ${HADOOP_SECONDARYNAMENODE_OPTS}"
   ;;
   snapshotDiff)
@@ -196,6 +212,7 @@ case ${COMMAND} in
   zkfc)
     daemon="true"
     CLASS='org.apache.hadoop.hdfs.tools.DFSZKFailoverController'
+    hadoop_debug "Appending HADOOP_ZKFC_OPTS onto HADOOP_OPTS"
     HADOOP_OPTS="${HADOOP_OPTS} ${HADOOP_ZKFC_OPTS}"
   ;;
   -*)
@@ -236,8 +253,6 @@ fi
 hadoop_add_param HADOOP_OPTS Xmx "${JAVA_HEAP_MAX}"
 hadoop_finalize
 
-export CLASSPATH
-
 if [[ -n "${daemon}" ]]; then
   if [[ -n "${secure_service}" ]]; then
     hadoop_secure_daemon_handler \
diff --git a/hadoop-mapreduce-project/bin/mapred b/hadoop-mapreduce-project/bin/mapred
index cbfdc7e7d0..8f3063774f 100755
--- a/hadoop-mapreduce-project/bin/mapred
+++ b/hadoop-mapreduce-project/bin/mapred
@@ -64,13 +64,15 @@ shift
 
 case ${COMMAND} in
   mradmin|jobtracker|tasktracker|groups)
-    echo "Sorry, the ${COMMAND} command is no longer supported."
-    echo "You may find similar functionality with the \"yarn\" shell command."
+    hadoop_error "Sorry, the ${COMMAND} command is no longer supported."
+    hadoop_error "You may find similar functionality with the \"yarn\" shell command."
     hadoop_exit_with_usage 1
   ;;
   archive)
     CLASS=org.apache.hadoop.tools.HadoopArchives
+    hadoop_debug "Injecting TOOL_PATH into CLASSPATH"
     hadoop_add_classpath "${TOOL_PATH}"
+    hadoop_debug "Appending HADOOP_CLIENT_OPTS onto HADOOP_OPTS"
     HADOOP_OPTS="${HADOOP_OPTS} ${HADOOP_CLIENT_OPTS}"
   ;;
   classpath)
@@ -80,12 +82,15 @@ case ${COMMAND} in
   ;;
   distcp)
     CLASS=org.apache.hadoop.tools.DistCp
+    hadoop_debug "Injecting TOOL_PATH into CLASSPATH"
     hadoop_add_classpath "${TOOL_PATH}"
+    hadoop_debug "Appending HADOOP_CLIENT_OPTS onto HADOOP_OPTS"
     HADOOP_OPTS="${HADOOP_OPTS} ${HADOOP_CLIENT_OPTS}"
   ;;
   historyserver)
     daemon="true"
     CLASS=org.apache.hadoop.mapreduce.v2.hs.JobHistoryServer
+    hadoop_debug "Appending HADOOP_JOB_HISTORYSERVER_OPTS onto HADOOP_OPTS"
     HADOOP_OPTS="${HADOOP_OPTS} ${HADOOP_JOB_HISTORYSERVER_OPTS}"
     if [ -n "${HADOOP_JOB_HISTORYSERVER_HEAPSIZE}" ]; then
       JAVA_HEAP_MAX="-Xmx${HADOOP_JOB_HISTORYSERVER_HEAPSIZE}m"
@@ -97,6 +102,7 @@ case ${COMMAND} in
   ;;
   pipes)
     CLASS=org.apache.hadoop.mapred.pipes.Submitter
+    hadoop_debug "Appending HADOOP_CLIENT_OPTS onto HADOOP_OPTS"
     HADOOP_OPTS="${HADOOP_OPTS} ${HADOOP_CLIENT_OPTS}"
   ;;
   queue)
@@ -104,10 +110,12 @@ case ${COMMAND} in
   ;;
   sampler)
     CLASS=org.apache.hadoop.mapred.lib.InputSampler
+    hadoop_debug "Appending HADOOP_CLIENT_OPTS onto HADOOP_OPTS"
     HADOOP_OPTS="${HADOOP_OPTS} ${HADOOP_CLIENT_OPTS}"
   ;;
   version)
     CLASS=org.apache.hadoop.util.VersionInfo
+    hadoop_debug "Appending HADOOP_CLIENT_OPTS onto HADOOP_OPTS"
     HADOOP_OPTS="${HADOOP_OPTS} ${HADOOP_CLIENT_OPTS}"
   ;;
   -*|*)
@@ -130,8 +138,6 @@ fi
 hadoop_add_param HADOOP_OPTS Xmx "${JAVA_HEAP_MAX}"
 hadoop_finalize
 
-export CLASSPATH
-
 if [[ -n "${daemon}" ]]; then
   if [[ -n "${secure_service}" ]]; then
     hadoop_secure_daemon_handler "${HADOOP_DAEMON_MODE}" "${COMMAND}"\
diff --git a/hadoop-yarn-project/hadoop-yarn/bin/yarn b/hadoop-yarn-project/hadoop-yarn/bin/yarn
index dfef8112f0..371d23d712 100644
--- a/hadoop-yarn-project/hadoop-yarn/bin/yarn
+++ b/hadoop-yarn-project/hadoop-yarn/bin/yarn
@@ -72,6 +72,7 @@ shift
 case "${COMMAND}" in
   application|applicationattempt|container)
     CLASS=org.apache.hadoop.yarn.client.cli.ApplicationCLI
+    hadoop_debug "Append YARN_CLIENT_OPTS onto YARN_OPTS"
     YARN_OPTS="${YARN_OPTS} ${YARN_CLIENT_OPTS}"
     set -- "${COMMAND}" "$@"
   ;;
@@ -82,10 +83,12 @@ case "${COMMAND}" in
   ;;
   daemonlog)
     CLASS=org.apache.hadoop.log.LogLevel
+    hadoop_debug "Append YARN_CLIENT_OPTS onto YARN_OPTS"
     YARN_OPTS="${YARN_OPTS} ${YARN_CLIENT_OPTS}"
   ;;
   jar)
     CLASS=org.apache.hadoop.util.RunJar
+    hadoop_debug "Append YARN_CLIENT_OPTS onto YARN_OPTS"
     YARN_OPTS="${YARN_OPTS} ${YARN_CLIENT_OPTS}"
   ;;
   historyserver)
@@ -97,15 +100,18 @@ case "${COMMAND}" in
   ;;
   logs)
     CLASS=org.apache.hadoop.yarn.logaggregation.LogDumper
+    hadoop_debug "Append YARN_CLIENT_OPTS onto YARN_OPTS"
     YARN_OPTS="${YARN_OPTS} ${YARN_CLIENT_OPTS}"
   ;;
   node)
     CLASS=org.apache.hadoop.yarn.client.cli.NodeCLI
+    hadoop_debug "Append YARN_CLIENT_OPTS onto YARN_OPTS"
     YARN_OPTS="${YARN_OPTS} ${YARN_CLIENT_OPTS}"
   ;;
   nodemanager)
     daemon="true"
     CLASS='org.apache.hadoop.yarn.server.nodemanager.NodeManager'
+    hadoop_debug "Append YARN_NODEMANAGER_OPTS onto YARN_OPTS"
     YARN_OPTS="${YARN_OPTS} ${YARN_NODEMANAGER_OPTS}"
     if [[ -n "${YARN_NODEMANAGER_HEAPSIZE}" ]]; then
       JAVA_HEAP_MAX="-Xmx${YARN_NODEMANAGER_HEAPSIZE}m"
@@ -114,6 +120,7 @@ case "${COMMAND}" in
   proxyserver)
     daemon="true"
     CLASS='org.apache.hadoop.yarn.server.webproxy.WebAppProxyServer'
+    hadoop_debug "Append YARN_PROXYSERVER_OPTS onto YARN_OPTS"
     YARN_OPTS="${YARN_OPTS} ${YARN_PROXYSERVER_OPTS}"
     if [[ -n "${YARN_PROXYSERVER_HEAPSIZE}" ]]; then
       JAVA_HEAP_MAX="-Xmx${YARN_PROXYSERVER_HEAPSIZE}m"
@@ -123,17 +130,20 @@ case "${COMMAND}" in
     daemon="true"
     CLASS='org.apache.hadoop.yarn.server.resourcemanager.ResourceManager'
     YARN_OPTS="${YARN_OPTS} ${YARN_RESOURCEMANAGER_OPTS}"
+    hadoop_debug "Append YARN_RESOURCEMANAGER_OPTS onto YARN_OPTS"
     if [[ -n "${YARN_RESOURCEMANAGER_HEAPSIZE}" ]]; then
       JAVA_HEAP_MAX="-Xmx${YARN_RESOURCEMANAGER_HEAPSIZE}m"
     fi
   ;;
   rmadmin)
     CLASS='org.apache.hadoop.yarn.client.cli.RMAdminCLI'
+    hadoop_debug "Append YARN_CLIENT_OPTS onto YARN_OPTS"
     YARN_OPTS="${YARN_OPTS} ${YARN_CLIENT_OPTS}"
   ;;
   timelineserver)
     daemon="true"
     CLASS='org.apache.hadoop.yarn.server.applicationhistoryservice.ApplicationHistoryServer'
+    hadoop_debug "Append YARN_TIMELINESERVER_OPTS onto YARN_OPTS"
     YARN_OPTS="${YARN_OPTS} ${YARN_TIMELINESERVER_OPTS}"
     if [[ -n "${YARN_TIMELINESERVER_HEAPSIZE}" ]]; then
       JAVA_HEAP_MAX="-Xmx${YARN_TIMELINESERVER_HEAPSIZE}m"
@@ -141,6 +151,7 @@ case "${COMMAND}" in
   ;;
   version)
     CLASS=org.apache.hadoop.util.VersionInfo
+    hadoop_debug "Append YARN_CLIENT_OPTS onto YARN_OPTS"
     YARN_OPTS="${YARN_OPTS} ${YARN_CLIENT_OPTS}"
   ;;
   -*)
@@ -153,6 +164,8 @@ esac
 
 # set HADOOP_OPTS to YARN_OPTS so that we can use
 # finalize, etc, without doing anything funky
+hadoop_debug "Resetting HADOOP_OPTS=YARN_OPTS"
+# shellcheck disable=SC2034
 HADOOP_OPTS="${YARN_OPTS}"
 
 daemon_outfile="${HADOOP_LOG_DIR}/hadoop-${HADOOP_IDENT_STRING}-${COMMAND}-${HOSTNAME}.out"
@@ -180,8 +193,6 @@ hadoop_add_param HADOOP_OPTS yarn.root.logger "-Dyarn.root.logger=${YARN_ROOT_LO
 
 hadoop_finalize
 
-export CLASSPATH
-
 if [[ -n "${daemon}" ]]; then
   if [[ -n "${secure_service}" ]]; then
     hadoop_secure_daemon_handler "${HADOOP_DAEMON_MODE}" "${COMMAND}" \