:original_name: mrs_01_1690.html .. _mrs_01_1690: FAQ === - :ref:`NameNode Startup Is Slow ` - :ref:`DataNode Is Normal but Cannot Report Data Blocks ` - :ref:`HDFS WebUI Cannot Properly Update Information About Damaged Data ` - :ref:`Why Does the Distcp Command Fail in the Secure Cluster, Causing an Exception? ` - :ref:`Why Does DataNode Fail to Start When the Number of Disks Specified by dfs.datanode.data.dir Equals dfs.datanode.failed.volumes.tolerated? ` - :ref:`Failed to Calculate the Capacity of a DataNode when Multiple data.dir Directories Are Configured in a Disk Partition ` - :ref:`Standby NameNode Fails to Be Restarted When the System Is Powered off During Metadata (Namespace) Storage ` - :ref:`Why Data in the Buffer Is Lost If a Power Outage Occurs During Storage of Small Files ` - :ref:`Why Does Array Border-crossing Occur During FileInputFormat Split? ` - :ref:`Why Is the Storage Type of File Copies DISK When the Tiered Storage Policy Is LAZY_PERSIST? ` - :ref:`The HDFS Client Is Unresponsive When the NameNode Is Overloaded for a Long Time ` - :ref:`Can I Delete or Modify the Data Storage Directory in DataNode? ` - :ref:`Blocks Miss on the NameNode UI After the Successful Rollback ` - :ref:`Why Is "java.net.SocketException: No buffer space available" Reported When Data Is Written to HDFS ` - :ref:`Why are There Two Standby NameNodes After the active NameNode Is Restarted? ` - :ref:`When Does a Balance Process in HDFS, Shut Down and Fail to be Executed Again? ` - :ref:`"This page can't be displayed" Is Displayed When Internet Explorer Fails to Access the Native HDFS UI ` - :ref:`NameNode Fails to Be Restarted Due to EditLog Discontinuity ` .. toctree:: :maxdepth: 1 :hidden: namenode_startup_is_slow datanode_is_normal_but_cannot_report_data_blocks hdfs_webui_cannot_properly_update_information_about_damaged_data why_does_the_distcp_command_fail_in_the_secure_cluster_causing_an_exception why_does_datanode_fail_to_start_when_the_number_of_disks_specified_by_dfs.datanode.data.dir_equals_dfs.datanode.failed.volumes.tolerated failed_to_calculate_the_capacity_of_a_datanode_when_multiple_data.dir_directories_are_configured_in_a_disk_partition standby_namenode_fails_to_be_restarted_when_the_system_is_powered_off_during_metadata_namespace_storage why_data_in_the_buffer_is_lost_if_a_power_outage_occurs_during_storage_of_small_files why_does_array_border-crossing_occur_during_fileinputformat_split why_is_the_storage_type_of_file_copies_disk_when_the_tiered_storage_policy_is_lazy_persist the_hdfs_client_is_unresponsive_when_the_namenode_is_overloaded_for_a_long_time can_i_delete_or_modify_the_data_storage_directory_in_datanode blocks_miss_on_the_namenode_ui_after_the_successful_rollback why_is_java.net.socketexception_no_buffer_space_available_reported_when_data_is_written_to_hdfs why_are_there_two_standby_namenodes_after_the_active_namenode_is_restarted when_does_a_balance_process_in_hdfs_shut_down_and_fail_to_be_executed_again this_page_cant_be_displayed_is_displayed_when_internet_explorer_fails_to_access_the_native_hdfs_ui namenode_fails_to_be_restarted_due_to_editlog_discontinuity