Prerequisites for fixing issues after NameNode migration

Learn about the prerequisites that you must perform before fixing issues related to your Database Catalog and Virtual Warehouses after migrating your HDFS NameNode.

Ensure that you meet the following prerequisites before addressing the issues related to Cloudera Data Warehouse:

Login to Cloudera Manager and click Clusters > HIVE_ON_TEZ.
From the HIVE_ON_TEZ service page, click Actions > Download Client Configuration.
Save and extract the contents of the hive_on_tez-1-clientconfig.zip file.
Open the hdfs-site.xml configuration file and identify the configuration (dfs.ha.namenodes.<NameNode name>) containing the names of the NameNodes. Make a note of the value.
```
 <property>
    <name>dfs.ha.namenodes.ns1</name>
    <value>namenode1546339554,namenode1546335674</value>
  </property>
```

Identify and note down all the NameNode specific configuration from the hdfs-site.xml configuration file.

<property>
    <name>dfs.ha.namenodes.ns1</name>
    <value>namenode1546339554,namenode1546335674</value>
  </property>
  <property>
    <name>dfs.namenode.rpc-address.ns1.namenode1546339554</name>
    <value>[***HOSTNAME***]:[***PORT***]</value>
  </property>
  <property>
    <name>dfs.namenode.servicerpc-address.ns1.namenode1546339554</name>
    <value>[***HOSTNAME***]:[***PORT***]</value>
  </property>
  <property>
    <name>dfs.namenode.http-address.ns1.namenode1546339554</name>
    <value>[***HOSTNAME***]:[***PORT***]</value>
  </property>
  <property>
    <name>dfs.namenode.https-address.ns1.namenode1546339554</name>
    <value>[***HOSTNAME***]:[***PORT***]</value>
  </property>
  <property>
    <name>dfs.namenode.rpc-address.ns1.namenode1546335674</name>
    <value>[***HOSTNAME***]:[***PORT***]</value>
  </property>
  <property>
    <name>dfs.namenode.servicerpc-address.ns1.namenode1546335674</name>
    <value>[***HOSTNAME***]:[***PORT***]</value>
  </property>
  <property>
    <name>dfs.namenode.http-address.ns1.namenode1546335674</name>
    <value>[***HOSTNAME***]:[***PORT***]</value>
  </property>
  <property>
    <name>dfs.namenode.https-address.ns1.namenode1546335674</name>
    <value>[***HOSTNAME***]:[***PORT***]</value>
  </property>

Perform the steps described in the following topics to address issues specific to your Database Catalog and Hive or Impala Virtual Warehouses.