Answer / Rahulendra Singh

In Apache HDFS (Hadoop Distributed File System), Heartbeat is a mechanism used to monitor the health and availability of DataNodes (servers) in the cluster. Each DataNode sends a heartbeat message to the NameNode periodically, usually every 3 seconds by default. The NameNode uses these heartbeats to keep track of which blocks are stored on which DataNodes and to detect any failures or errors.nnIf a DataNode fails to send a heartbeat for more than three times the configured timeout period (default is 10 minutes), the NameNode marks it as dead and replicates any missing data from other DataNodes to ensure data integrity. This mechanism allows HDFS to be highly fault-tolerant and maintain data availability even in the event of node failures.

Tell me two most commonly used commands in HDFS?

1 Answers  

---

How will you perform the inter cluster data copying work in hdfs?

1 Answers  

---

Define data integrity?

1 Answers  

---

Explain how indexing in hdfs is done?

1 Answers  

---

How to create directory in HDFS?

1 Answers  

---

What is HDFS?

1 Answers  

---

What does hdfs mean?

1 Answers  

---

Can you modify the file present in hdfs?

1 Answers  

---

What is the procedure to create users in HDFS and how to allocate Quota to them?

1 Answers  

---

Why rack awareness algorithm is used in hadoop?

1 Answers  

---

Why HDFS?

1 Answers  

---

What do you mean by metadata in HDFS? Where is it stored in Hadoop?

1 Answers  

---