HDFS service ports
What is the Datanode control port number?
HDFS service ports
|Service||Servers||Default Ports Used|
|NameNode WebUI||Master Nodes (NameNode and any back-up NameNodes)||50070|
|NameNode metadata service||8020/ 9000|
|DataNode||All Slave Nodes||50075|
What port does Hadoop use?
hadoop – Default Namenode port of HDFS is 50070.
What is the procedure to decommission Datanode?
Decommissioning process of the data node ensures that data is transferred to other nodes so that the existing replication factor is not disturbed.
- Check NameNode UI for available data nodes and their status.
- dfs.hosts.exclude property.
- Update dfs.exclude file.
- Run refreshNodes command.
What happens when a Datanode or a NameNode fails?
A block report of a particular Datanode contains information about all the blocks on that resides on the corresponding Datanode. When Namenode doesn’t receive any heartbeat message for 10 minutes(ByDefault) from a particular Datanode then corresponding Datanode is considered Dead or failed by Namenode.
How do I find my server port for hive?
Go to Summary on the hive tab and you will see a list of all hiveservers metastore services etc. Click on the hiveserver2 one and you see the host its running on.
Is HBase good for structured data?
For both semi-structured as well as structured data, HBase supports well. There is no concept of fixed columns schema in HBase because it is schema-less. Hence, it defines only column families. Due to high security and easy management characteristics of HBase, it offers unprecedented high write throughput.
How do I access the Hadoop web interface?
Enter the URL as http://localhost:50070/ in web browser and to point to port number 50070 on localhost host name in pseudo-distributed mode. In Fully distributed mode, replace the ‘localhost’ with actual host name of machine on cluster.
How do I install Hadoop on Windows 10?
Steps to Install Hadoop
- Install Java JDK 1.8.
- Download Hadoop and extract and place under C drive.
- Set Path in Environment Variables.
- Config files under Hadoop directory.
- Create folder datanode and namenode under data directory.
- Edit HDFS and YARN files.
- Set Java Home environment in Hadoop environment.
- Setup Complete.
How do you decommission a DataNode in hortonworks?
Find and click the FQDN of the host on which the DataNode component resides. Using the Actions control, click Selected Hosts > DataNodes > Decommission. The UI shows Decommissioning status while in process.
How do you decommission a DataNode in cloudera?
Use the following instructions to decommission DataNodes in your cluster: On the NameNode host machine, edit the /dfs. exclude file and add the list of DataNodes hostnames (separated by a newline character). where is the directory for storing the Hadoop configuration files.
What happens when a DataNode fails?
When NameNode notices that it has not received a heartbeat message from a datanode after a certain amount of time (usually 10 minutes by default), the data node is marked as dead. Since blocks will be under-replicated, the system begins replicating the blocks that were stored on the dead DataNode.
What message is generated by a DataNode to indicate it’s connectivity to NameNode?
A Heartbeat is a signal from Datanodeto Name node to indicate that Data node is alive.