YARN-2807. Option "--forceactive" not works as described in usage of

"yarn rmadmin -transitionToActive". Contributed by Masatake Iwasaki

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/ha/HAAdmin.java

@@ -69,15 +69,15 @@ public abstract class HAAdmin extends Configured implements Tool {
   protected final static Map<String, UsageInfo> USAGE =
     ImmutableMap.<String, UsageInfo>builder()
     .put("-transitionToActive",
-        new UsageInfo("<serviceId> [--"+FORCEACTIVE+"]", "Transitions the service into Active state"))
+        new UsageInfo("[--"+FORCEACTIVE+"] <serviceId>", "Transitions the service into Active state"))
     .put("-transitionToStandby",
         new UsageInfo("<serviceId>", "Transitions the service into Standby state"))
     .put("-failover",
         new UsageInfo("[--"+FORCEFENCE+"] [--"+FORCEACTIVE+"] <serviceId> <serviceId>",
             "Failover from the first service to the second.\n" +
-            "Unconditionally fence services if the "+FORCEFENCE+" option is used.\n" +
+            "Unconditionally fence services if the --"+FORCEFENCE+" option is used.\n" +
             "Try to failover to the target service even if it is not ready if the " + 
-            FORCEACTIVE + " option is used."))
+            "--" + FORCEACTIVE + " option is used."))
     .put("-getServiceState",
         new UsageInfo("<serviceId>", "Returns the state of the service"))
     .put("-checkHealth",
@@ -228,7 +228,7 @@ public abstract class HAAdmin extends Configured implements Tool {
             "Refusing to manually manage HA state, since it may cause\n" +
             "a split-brain scenario or other incorrect state.\n" +
             "If you are very sure you know what you are doing, please \n" +
-            "specify the " + FORCEMANUAL + " flag.");
+            "specify the --" + FORCEMANUAL + " flag.");
         return false;
       } else {
         LOG.warn("Proceeding with manual HA state management even though\n" +
@@ -462,7 +462,7 @@ public abstract class HAAdmin extends Configured implements Tool {
   
   private boolean confirmForceManual() throws IOException {
      return ToolRunner.confirmPrompt(
-        "You have specified the " + FORCEMANUAL + " flag. This flag is " +
+        "You have specified the --" + FORCEMANUAL + " flag. This flag is " +
         "dangerous, as it can induce a split-brain scenario that WILL " +
         "CORRUPT your HDFS namespace, possibly irrecoverably.\n" +
         "\n" +

hadoop-yarn-project/CHANGES.txt

@@ -186,6 +186,9 @@ Release 2.7.0 - UNRELEASED
     YARN-3019. Make work-preserving-recovery the default mechanism for RM 
     recovery. (Jian He via junping_du)
 
+    YARN-2807. Option "--forceactive" not works as described in usage of
+    "yarn rmadmin -transitionToActive". (Masatake Iwasaki via xgong)
+
   OPTIMIZATIONS
 
   BUG FIXES

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-site/src/site/apt/ResourceManagerHA.apt.vm

@@ -208,6 +208,7 @@ ResourceManager High Availability
 +---+
 
    If automatic failover is enabled, you can not use manual transition command.
+   Though you can override this by --forcemanual flag, you need caution.
 
 +---+
  $ yarn rmadmin -transitionToStandby rm1

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-site/src/site/apt/YarnCommands.apt.vm

@@ -246,13 +246,19 @@ YARN Commands
   Usage:
 
 ----
-  yarn rmadmin [-refreshQueues] [-refreshNodes] [-refreshUserToGroupsMapping]
+  yarn rmadmin [-refreshQueues]
-                      [-refreshSuperUserGroupsConfiguration] [-refreshAdminAcls]
+               [-refreshNodes]
-                      [-refreshServiceAcl] [-getGroups [username]] [-help [cmd]]
+               [-refreshUserToGroupsMapping] 
-                      [-transitionToActive <serviceId>]
+               [-refreshSuperUserGroupsConfiguration]
-                      [-transitionToStandby <serviceId>]
+               [-refreshAdminAcls] 
+               [-refreshServiceAcl]
+               [-getGroups [username]]
+               [-transitionToActive [--forceactive] [--forcemanual] <serviceId>]
+               [-transitionToStandby [--forcemanual] <serviceId>]
+               [-failover [--forcefence] [--forceactive] <serviceId1> <serviceId2>]
                [-getServiceState <serviceId>]
                [-checkHealth <serviceId>]
+               [-help [cmd]]
 ----
 
 *---------------+--------------+
@@ -277,14 +283,26 @@ YARN Commands
 *---------------+--------------+
 | -getGroups [username] | Get groups the specified user belongs to.
 *---------------+--------------+
-| -help [cmd] | Displays help for the given command or all commands if none is
+| -transitionToActive [--forceactive] [--forcemanual] \<serviceId\> |
-|             | specified.
+|               | Transitions the service into Active state.
+|               | Try to make the target active
+|               | without checking that there is no active node
+|               | if the --forceactive option is used.
+|               | This command can not be used if automatic failover is enabled.
+|               | Though you can override this by --forcemanual option,
+|               | you need caution.
 *---------------+--------------+
-| -transitionToActive \<serviceId\> | Transitions the service into Active
+| -transitionToStandby [--forcemanual] \<serviceId\> |
-|                                   | state.
+|               | Transitions the service into Standby state.
+|               | This command can not be used if automatic failover is enabled.
+|               | Though you can override this by --forcemanual option,
+|               | you need caution.
 *---------------+--------------+
-| -transitionToStandby \<serviceId\> | Transitions the service into Standby
+| -failover [--forceactive] \<serviceId1\> \<serviceId2\> |
-|                                    | state.
+|               | Initiate a failover from serviceId1 to serviceId2.
+|               | Try to failover to the target service even if it is not ready
+|               | if the --forceactive option is used.
+|               | This command can not be used if automatic failover is enabled.
 *---------------+--------------+
 | -getServiceState \<serviceId\> | Returns the state of the service.
 *---------------+--------------+
@@ -292,6 +310,10 @@ YARN Commands
 |                            | check. The RMAdmin tool will exit with a
 |                            | non-zero exit code if the check fails.
 *---------------+--------------+
+| -help [cmd] | Displays help for the given command or all commands if none is
+|             | specified.
+*---------------+--------------+
+
 
   Runs ResourceManager admin client