Merge pull request #220187 from nadiacps/main

Add note that upgrading existing storage with ADLS gen2 capabilities is not supported

Author: prmerger-automator[bot]

articles/hdinsight/hadoop/apache-hadoop-on-premises-migration-best-practices-storage.md

@@ -104,6 +104,9 @@ One of the following formats can be used to access data that is stored in ADLS G
 - `abfs:///`: Access the default Data Lake Storage for the cluster.
 - `abfs://file_system@account_name.dfs.core.windows.net`: Used when communicating with a non-default Data Lake Storage.
 
+>[!NOTE]
+> Upgrading the primary or secondary storage account of a running cluster with Azure Data Lake Storage Gen2 capabilities is not supported. To change the storage type of an existing HDInsight cluster to Data Lake Storage Gen2, you will need to recreate the cluster and select an hierarchical namespace enabled storage account.
+
 For more information, see the following articles:
 
 - [Introduction to Azure Data Lake Storage Gen2](../../storage/blobs/data-lake-storage-introduction.md)
@@ -216,4 +219,4 @@ For more information, see [Add additional storage accounts to HDInsight](../hdin
 
 ## Next steps
 
-Read the next article in this series: [Data migration best practices for on-premises to Azure HDInsight Hadoop migration](apache-hadoop-on-premises-migration-best-practices-data-migration.md).
+Read the next article in this series: [Data migration best practices for on-premises to Azure HDInsight Hadoop migration](apache-hadoop-on-premises-migration-best-practices-data-migration.md).

articles/hdinsight/hdinsight-hadoop-compare-storage-options.md

@@ -62,6 +62,9 @@ You can create clusters using combinations of services for primary and optional
 Azure HDInsight does not store customer data. The primary means of storage for a cluster are its associated storage accounts. You can attach your cluster to an existing storage account, or create a new storage account during the cluster creation process. If a new account is created, it will be created as a locally redundant storage (LRS) account, and will satisfy in-region data residency requirements including those specified in the [Trust Center](https://azuredatacentermap.azurewebsites.net).
 
 You can validate that HDInsight is properly configured to store data in a single region by ensuring that the storage account associated with your HDInsight is LRS or another storage option mentioned on [Trust Center](https://azuredatacentermap.azurewebsites.net).
+
+>[!NOTE]
+> Upgrading the primary or secondary storage account of a running cluster with Azure Data Lake Storage Gen2 capabilities is not supported. To change the storage type of an existing HDInsight cluster to Data Lake Storage Gen2, you will need to recreate the cluster and select an hierarchical namespace enabled storage account.
  
 ## Next steps