Dear Learner,


Hope you are doing well.


Please find the below the solutions related to your query.

 

1. namenode and data node are in same directory ?..what is the port number of these ? What about resource manager ,node manager ,secondary namenode ?


Solution:- Whenever we are setting up a single node cluster then we use different directory for namenode and datanode to save metadata and actual data.


For eg :- In edureka vm we have created separate directories for namenode and datanode.




In a cluster port number are randomly assigned to the daemons, we cannot restrict a specific port number to particular deamon.


Resourcemanager is used to schedule the task and node manager help to execute the task one by one, if we talk about secondarynamenode, in hadoop 2.x this daemons doesn't plays any role, it is used only in hadoop 1.x to store the back up of namenode.


2.can we see the metadata of namenode ? Fs image and edit logs can be seen or not ? I want to see .


Namenode stores the metadata in form of fsimage and edit logs files, you can see the files but the text written inside the file is not readable.


Please refer the below given link to check the path for fsimage and edit logs file.


3. Can u please elaborate single node cluster in detail ? Where is the namenode store I.e where are all the daemons store ...what is their path ? How can see the details of all the daemons ?


Single node is a cluster in which all the daemons runs in single machine on specific port number which are randomly given by the cluster, in cluster we cannot see the storage of daemons only with the help of jps or sudo jps command we can see the status of daemon.


Feel free to contact us in case you have any query.

 


190715