CODEWITHSUNDEEP
hadoophdfs
user1647267
user1647267

Reputation: 39

When will HDFS be unavailable?

Name node is the single point of failure for HDFS. Is this correct?

Then what about Jobtracker? If Jobtracker fails, is HDFS available?

Upvotes: 0

Views: 2942

Answers (2)

Arnon Rotem-Gal-Oz
Arnon Rotem-Gal-Oz

Reputation: 25909

As Ambar mentioned HDFS as in the file system does not depend on the JobTracker. The current released version of Hadoop does not support Namenode high availability out of the box but you can work around it (e.g. deploy the namenode using a traditional clustering solution of active/passive with shared storage). The next release (2.0/0.23) does fix the namenode availability issue.

You can read more about it in a blog post by Aaron Myers "High Availability for the Hadoop Distributed File System (HDFS)"

If the JobTracker is not available you cannot execute map/reduce jobs

Upvotes: 0

Ambar
Ambar

Reputation: 132

HDFS is completely independent of the Jobtracker. As long as at least the NN is up, HDFS is nominally usable, with overall degradation dependent on the number of Datanodes that are down.

Upvotes: 1

Related Questions