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What occurs if a user submits a new job when NameNode is down?
Hadoop's NameNode is a single point of failure, making it impossible for users to submit or run new jobs. The user must wait for NameNode to restart before performing any jobs since if NameNode is down, the job may fail.
Hadoop’s NameNode is a single point of failure, making it impossible for users to submit or run new jobs. The user must wait for NameNode to restart before performing any jobs since if NameNode is down, the job may fail.
See lessWhat are the Secondary NameNode’s functions?
Secondary NameNode's functions are as follows: FsImage, which keeps a copy of both the FsImage and EditLog files. NameNode failure: The Secondary NameNode's FsImage can be used to reconstruct the NameNode if it crashes. Checkpoint: Secondary NameNode uses this checkpoint to ensure that HDFS data isRead more
Secondary NameNode’s functions are as follows:
Explain “rack awareness.”
When reading or writing any file located closer to the neighboring rack to the Read or Write request in the Hadoop cluster, Namenode leverages the Datanode to reduce network traffic. Namenode keeps track of each DataNode's rack id, which is known as rack awareness.
When reading or writing any file located closer to the neighboring rack to the Read or Write request in the Hadoop cluster, Namenode leverages the Datanode to reduce network traffic.
Namenode keeps track of each DataNode’s rack id, which is known as rack awareness.
See lessHow do you turn off the HDFS Data Node’s Block Scanner?
Set dfs.datanode.scan.period.hours to 0 to disable Block Scanner on HDFS Data Node.
Set dfs.datanode.scan.period.hours to 0 to disable Block Scanner on HDFS Data Node.
See lessList the standard port numbers on which Hadoop’s task tracker, NameNode, and job tracker operate.
Hadoop’s task and job trackers all run on the following default port numbers: The task tracker runs on the 50060 port. NameNode runs on the 50070 port. Job Tracker runs on the 50030 port.
Hadoop’s task and job trackers all run on the following default port numbers:
What does FIFO entail?
FIFO is a scheduling algorithm for Hadoop jobs.
FIFO is a scheduling algorithm for Hadoop jobs.
See lessWhat is big data?
Big data is data of immense volume, variety, and velocity. It entails larger data sets from various data sources.
Big data is data of immense volume, variety, and velocity. It entails larger data sets from various data sources.
See lessWhat does Hadoop’s Heartbeat mean?
NameNode and DataNode converse with one another in Hadoop. The heartbeat is the regular signal DataNode sends to NameNode to confirm its presence.
NameNode and DataNode converse with one another in Hadoop. The heartbeat is the regular signal DataNode sends to NameNode to confirm its presence.
See lessHow can you achieve security in Hadoop?
For Hadoop security, take the following actions: 1) Secure the client's authentication channel with the server, and give the client time-stamped documents. 2) The client asks TGS for a service ticket using the time-stamped information. 3) The client uses a service ticket to self-authenticate to a paRead more
For Hadoop security, take the following actions:
1) Secure the client’s authentication channel with the server, and give the client time-stamped documents.
2) The client asks TGS for a service ticket using the time-stamped information.
3) The client uses a service ticket to self-authenticate to a particular server in the last phase.
See lessDescribe the distributed Hadoop file system.
Scalable distributed file systems like S3, HFTP FS, FS, and HDFS are compatible with Hadoop. The Google File System is the foundation for the Hadoop Distributed File System. This file system is made to be easily operable on a sizable cluster of the computer system.
Scalable distributed file systems like S3, HFTP FS, FS, and HDFS are compatible with Hadoop. The Google File System is the foundation for the Hadoop Distributed File System. This file system is made to be easily operable on a sizable cluster of the computer system.
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