[2.x] Deprecated reserved node id '_must_join_elected_master_' that used by DetachClusterCommand and replace with '_must_join_elected_cluster_manager_'

server/src/main/java/org/opensearch/cluster/coordination/ClusterFormationFailureHelper.java

@@ -218,7 +218,8 @@ String getDescription() {
 
             assert clusterState.getLastCommittedConfiguration().isEmpty() == false;
 
-            if (clusterState.getLastCommittedConfiguration().equals(VotingConfiguration.MUST_JOIN_ELECTED_MASTER)) {
+            if (clusterState.getLastCommittedConfiguration().equals(VotingConfiguration.MUST_JOIN_ELECTED_MASTER)
+                || clusterState.getLastCommittedConfiguration().equals(VotingConfiguration.MUST_JOIN_ELECTED_CLUSTER_MANAGER)) {
                 return String.format(
                     Locale.ROOT,
                     "cluster-manager not discovered yet and this node was detached from its previous cluster, have discovered %s; %s",

server/src/main/java/org/opensearch/cluster/coordination/CoordinationMetadata.java

@@ -350,9 +350,16 @@ public String toString() {
     public static class VotingConfiguration implements Writeable, ToXContentFragment {
 
         public static final VotingConfiguration EMPTY_CONFIG = new VotingConfiguration(Collections.emptySet());
+        /**
+         * @deprecated As of 2.0, because supporting inclusive language, replaced by {@link #MUST_JOIN_ELECTED_CLUSTER_MANAGER}
+         */
+        @Deprecated
         public static final VotingConfiguration MUST_JOIN_ELECTED_MASTER = new VotingConfiguration(
             Collections.singleton("_must_join_elected_master_")
         );
+        public static final VotingConfiguration MUST_JOIN_ELECTED_CLUSTER_MANAGER = new VotingConfiguration(
+            Collections.singleton("_must_join_elected_cluster_manager_")
+        );
 
         private final Set<String> nodeIds;
 

server/src/main/java/org/opensearch/cluster/coordination/DetachClusterCommand.java

@@ -86,8 +86,8 @@ protected void processNodePaths(Terminal terminal, Path[] dataPaths, int nodeLoc
     // package-private for tests
     static Metadata updateMetadata(Metadata oldMetadata) {
         final CoordinationMetadata coordinationMetadata = CoordinationMetadata.builder()
-            .lastAcceptedConfiguration(CoordinationMetadata.VotingConfiguration.MUST_JOIN_ELECTED_MASTER)
-            .lastCommittedConfiguration(CoordinationMetadata.VotingConfiguration.MUST_JOIN_ELECTED_MASTER)
+            .lastAcceptedConfiguration(CoordinationMetadata.VotingConfiguration.MUST_JOIN_ELECTED_CLUSTER_MANAGER)
+            .lastCommittedConfiguration(CoordinationMetadata.VotingConfiguration.MUST_JOIN_ELECTED_CLUSTER_MANAGER)
             .term(0)
             .build();
         return Metadata.builder(oldMetadata).coordinationMetadata(coordinationMetadata).clusterUUIDCommitted(false).build();

server/src/test/java/org/opensearch/cluster/coordination/ClusterFormationFailureHelperTests.java

@@ -428,7 +428,7 @@ public void testDescriptionAfterDetachCluster() {
 
         final ClusterState clusterState = state(
             localNode,
-            VotingConfiguration.MUST_JOIN_ELECTED_MASTER.getNodeIds().toArray(new String[0])
+            VotingConfiguration.MUST_JOIN_ELECTED_CLUSTER_MANAGER.getNodeIds().toArray(new String[0])
         );
 
         assertThat(
@@ -899,4 +899,35 @@ public void testDescriptionAfterBootstrapping() {
         );
 
     }
+
+    /*
+     * Validate the Cluster State with deprecated VotingConfiguration.MUST_JOIN_ELECTED_MASTER can get correct ClusterFormationState description.
+     */
+    public void testDescriptionAfterDetachClusterWithDeprecatedMasterVotingConfiguration() {
+        final DiscoveryNode localNode = new DiscoveryNode("local", buildNewFakeTransportAddress(), Version.CURRENT);
+
+        final ClusterState clusterState = state(
+            localNode,
+            VotingConfiguration.MUST_JOIN_ELECTED_MASTER.getNodeIds().toArray(new String[0])
+        );
+
+        assertThat(
+            new ClusterFormationState(
+                Settings.EMPTY,
+                clusterState,
+                emptyList(),
+                emptyList(),
+                0L,
+                electionStrategy,
+                new StatusInfo(HEALTHY, "healthy-info")
+            ).getDescription(),
+            is(
+                "cluster-manager not discovered yet and this node was detached from its previous cluster, "
+                    + "have discovered []; "
+                    + "discovery will continue using [] from hosts providers and ["
+                    + localNode
+                    + "] from last-known cluster state; node term 0, last-accepted version 0 in term 0"
+            )
+        );
+    }
 }

test/framework/src/main/java/org/opensearch/cluster/coordination/CoordinationStateTestCluster.java

@@ -155,7 +155,7 @@ void reboot() {
                     .getLastAcceptedConfiguration()
                     .isEmpty()
                         ? CoordinationMetadata.VotingConfiguration.EMPTY_CONFIG
-                        : CoordinationMetadata.VotingConfiguration.MUST_JOIN_ELECTED_MASTER;
+                        : CoordinationMetadata.VotingConfiguration.MUST_JOIN_ELECTED_CLUSTER_MANAGER;
                 persistedState = new InMemoryPersistedState(
                     0L,
                     clusterState(0L, 0L, localNode, votingConfiguration, votingConfiguration, 0L)