HDDS-1474. ozone.scm.datanode.id config should take path for a dir and not a file

Author: Vivek Ratnavel Subramanian

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/scm/ScmConfigKeys.java

@@ -296,7 +296,7 @@ public final class ScmConfigKeys {
 
   public static final int OZONE_SCM_DEFAULT_PORT =
       OZONE_SCM_DATANODE_PORT_DEFAULT;
-  // File Name and path where datanode ID is to written to.
+  // The path where datanode ID is to be written to.
   // if this value is not set then container startup will fail.
   public static final String OZONE_SCM_DATANODE_ID = "ozone.scm.datanode.id";
 

hadoop-hdds/container-service/src/main/java/org/apache/hadoop/hdds/scm/HddsServerUtil.java

@@ -380,18 +380,19 @@ public static String getDefaultRatisDirectory(Configuration conf) {
    * @return the path of datanode id as string
    */
   public static String getDatanodeIdFilePath(Configuration conf) {
-    String dataNodeIDPath = conf.get(ScmConfigKeys.OZONE_SCM_DATANODE_ID);
-    if (dataNodeIDPath == null) {
+    String dataNodeIDDirPath = conf.get(ScmConfigKeys.OZONE_SCM_DATANODE_ID);
+    if (dataNodeIDDirPath == null) {
       File metaDirPath = ServerUtils.getOzoneMetaDirPath(conf);
       if (metaDirPath == null) {
         // this means meta data is not found, in theory should not happen at
         // this point because should've failed earlier.
         throw new IllegalArgumentException("Unable to locate meta data" +
             "directory when getting datanode id path");
       }
-      dataNodeIDPath = new File(metaDirPath,
-          ScmConfigKeys.OZONE_SCM_DATANODE_ID_PATH_DEFAULT).toString();
+      dataNodeIDDirPath = metaDirPath.toString();
     }
-    return dataNodeIDPath;
+    // Use default datanode id file name for file path
+    return new File(dataNodeIDDirPath,
+        ScmConfigKeys.OZONE_SCM_DATANODE_ID_PATH_DEFAULT).toString();
   }
 }

hadoop-hdds/container-service/src/test/java/org/apache/hadoop/ozone/container/common/TestDatanodeStateMachine.java

@@ -117,8 +117,7 @@ public void setUp() throws Exception {
     }
     conf.set(HddsConfigKeys.OZONE_METADATA_DIRS,
         new File(testRoot, "scm").getAbsolutePath());
-    path = Paths.get(path.toString(),
-        TestDatanodeStateMachine.class.getSimpleName() + ".id").toString();
+    path = new File(testRoot, "datnodeID").getAbsolutePath();
     conf.set(ScmConfigKeys.OZONE_SCM_DATANODE_ID, path);
     executorService = HadoopExecutors.newCachedThreadPool(
         new ThreadFactoryBuilder().setDaemon(true)
@@ -212,7 +211,8 @@ public void testDatanodeStateContext() throws IOException,
     // There is no mini cluster started in this test,
     // create a ID file so that state machine could load a fake datanode ID.
     File idPath = new File(
-        conf.get(ScmConfigKeys.OZONE_SCM_DATANODE_ID));
+        conf.get(ScmConfigKeys.OZONE_SCM_DATANODE_ID),
+        ScmConfigKeys.OZONE_SCM_DATANODE_ID_PATH_DEFAULT);
     idPath.delete();
     DatanodeDetails datanodeDetails = getNewDatanodeDetails();
     DatanodeDetails.Port port = DatanodeDetails.newPort(
@@ -334,7 +334,8 @@ public void testDatanodeStateContext() throws IOException,
   public void testDatanodeStateMachineWithIdWriteFail() throws Exception {
 
     File idPath = new File(
-        conf.get(ScmConfigKeys.OZONE_SCM_DATANODE_ID));
+        conf.get(ScmConfigKeys.OZONE_SCM_DATANODE_ID),
+        ScmConfigKeys.OZONE_SCM_DATANODE_ID_PATH_DEFAULT);
     idPath.delete();
     DatanodeDetails datanodeDetails = getNewDatanodeDetails();
     DatanodeDetails.Port port = DatanodeDetails.newPort(

hadoop-hdds/docs/content/Settings.md

@@ -106,7 +106,7 @@ Here is an example,
   {{< /highlight >}}
 
  * **ozone.scm.datanode.id** Data nodes generate a Unique ID called Datanode
- ID. This identity is written to the file specified by this path. *Data nodes
+ ID. This identity is written to the file datanode.id in a directory specified by this path. *Data nodes
     will create this path if it doesn't exist already.*
 
 Here is an  example,

hadoop-ozone/dist/src/main/compose/ozone-hdfs/docker-config

@@ -18,7 +18,7 @@ OZONE-SITE.XML_ozone.om.address=om
 OZONE-SITE.XML_ozone.om.http-address=om:9874
 OZONE-SITE.XML_ozone.scm.names=scm
 OZONE-SITE.XML_ozone.enabled=true
-OZONE-SITE.XML_ozone.scm.datanode.id=/data/datanode.id
+OZONE-SITE.XML_ozone.scm.datanode.id=/data
 OZONE-SITE.XML_ozone.scm.block.client.address=scm
 OZONE-SITE.XML_ozone.metadata.dirs=/data/metadata
 OZONE-SITE.XML_ozone.scm.client.address=scm

hadoop-ozone/dist/src/main/compose/ozone-om-ha/docker-config

@@ -21,7 +21,7 @@ OZONE-SITE.XML_ozone.om.address.om3=om3
 OZONE-SITE.XML_ozone.om.ratis.enable=true
 OZONE-SITE.XML_ozone.scm.names=scm
 OZONE-SITE.XML_ozone.enabled=True
-OZONE-SITE.XML_ozone.scm.datanode.id=/data/datanode.id
+OZONE-SITE.XML_ozone.scm.datanode.id=/data
 OZONE-SITE.XML_ozone.scm.block.client.address=scm
 OZONE-SITE.XML_ozone.metadata.dirs=/data/metadata
 OZONE-SITE.XML_ozone.handler.type=distributed

hadoop-ozone/dist/src/main/compose/ozone-recon/docker-config

@@ -18,7 +18,7 @@ OZONE-SITE.XML_ozone.om.address=om
 OZONE-SITE.XML_ozone.om.http-address=om:9874
 OZONE-SITE.XML_ozone.scm.names=scm
 OZONE-SITE.XML_ozone.enabled=True
-OZONE-SITE.XML_ozone.scm.datanode.id=/data/datanode.id
+OZONE-SITE.XML_ozone.scm.datanode.id=/data
 OZONE-SITE.XML_ozone.scm.block.client.address=scm
 OZONE-SITE.XML_ozone.metadata.dirs=/data/metadata
 OZONE-SITE.XML_ozone.recon.db.dir=/data/metadata/recon

hadoop-ozone/dist/src/main/compose/ozone/docker-config

@@ -18,7 +18,7 @@ OZONE-SITE.XML_ozone.om.address=om
 OZONE-SITE.XML_ozone.om.http-address=om:9874
 OZONE-SITE.XML_ozone.scm.names=scm
 OZONE-SITE.XML_ozone.enabled=True
-OZONE-SITE.XML_ozone.scm.datanode.id=/data/datanode.id
+OZONE-SITE.XML_ozone.scm.datanode.id=/data
 OZONE-SITE.XML_ozone.scm.block.client.address=scm
 OZONE-SITE.XML_ozone.metadata.dirs=/data/metadata
 OZONE-SITE.XML_ozone.handler.type=distributed

hadoop-ozone/dist/src/main/compose/ozoneblockade/docker-config

@@ -18,7 +18,7 @@ OZONE-SITE.XML_ozone.om.address=om
 OZONE-SITE.XML_ozone.om.http-address=om:9874
 OZONE-SITE.XML_ozone.scm.names=scm
 OZONE-SITE.XML_ozone.enabled=True
-OZONE-SITE.XML_ozone.scm.datanode.id=/data/datanode.id
+OZONE-SITE.XML_ozone.scm.datanode.id=/data
 OZONE-SITE.XML_ozone.scm.block.client.address=scm
 OZONE-SITE.XML_ozone.metadata.dirs=/data/metadata
 OZONE-SITE.XML_ozone.handler.type=distributed

hadoop-ozone/dist/src/main/compose/ozonefs/docker-config

@@ -19,7 +19,7 @@ OZONE-SITE.XML_ozone.om.address=om
 OZONE-SITE.XML_ozone.om.http-address=om:9874
 OZONE-SITE.XML_ozone.scm.names=scm
 OZONE-SITE.XML_ozone.enabled=True
-OZONE-SITE.XML_ozone.scm.datanode.id=/data/datanode.id
+OZONE-SITE.XML_ozone.scm.datanode.id=/data
 OZONE-SITE.XML_ozone.scm.block.client.address=scm
 OZONE-SITE.XML_ozone.metadata.dirs=/data/metadata
 OZONE-SITE.XML_ozone.handler.type=distributed