https://community.cloudera.com/t5/Support-Questions/Databode-uuid-unassigned/m-p/202366#M164372 <P>I have a 4 node cluster (2 master &amp; 2 Data nodes) - fresh Installation.</P><P>One of the Datanode is not coming up - 2018-05-22 14:37:56,024 ERROR datanode.DataNode (BPServiceActor.java:run(780)) - Initialization failed for Block pool &lt;registering&gt; (DatanodeUuid unassigned) service to Host1.infosolco.net/10.215.78.41:8020. Exiting. java.io.IOException: All specified directories are failed to load.</P><P>When I see the VERSION file, the :</P><P>root@Datanode02:/spark/hdfs/data/current # cat VERSION</P><P>#Tue May 22 14:00:02 PDT 2018</P><P>storageID=DS-0009b75a-e67a-4623-b7a2-12bf395c1d61</P><P>clusterID=CID-eb6df30f-7f16-4f94-826c-c7640e1e45a2</P><P>cTime=0</P><P>datanodeUuid=f005656a-673e-4c97-b25a-e19f04e1ec94</P><P>storageType=DATA_NODE</P><P>layoutVersion=-56</P><P>__________________</P><P>root@Datanode01:/spark/hdfs/data/current # cat VERSION</P><P>#Tue May 22 14:00:02 PDT 2018</P><P>storageID=DS-0009b75a-e67a-4623-b7a2-12bf395c1d61</P><P>clusterID=CID-eb6df30f-7f16-4f94-826c-c7640e1e45a2</P><P>cTime=0</P><P>datanodeUuid=f005656a-673e-4c97-b25a-e19f04e1ec94</P><P>storageType=DATA_NODE</P><P>layoutVersion=-56</P><P>I see both datanodes have same Uuid, and 2nd data node is not coming up.</P><P>Please suggest!</P> Wed, 23 May 2018 04:54:29 GMT BharathN 2018-05-23T04:54:29Z