Database Reference
In-Depth Information
Cassandra filesystem
Configuring Hadoop backed by Cassandra may give an illusion that we are replacing
HDFS because we take data from Cassandra and dump the results into it. It is not true. Ha-
doop still needs NameNode and DataNodes for various activities such as storing intermedi-
ate results, JAR files, and static data. Therefore, essentially, you are backed by no
single
point of failure
(
SPOF
) database, but you are still bounded by SPOFs such as NameNode
and JobTracker.
DataStax, a leading company in professional support for Cassandra, provides a solution to
this. Their enterprise offering of the Cassandra DataStax Enterprise product has a built-in
Cassandra File System
(
CFS
), which is HDFS-compatible. CFS smartly uses Cassandra
as underlying storage. What this gives to an end user is simplicity in configuration and no
need to have DataNode, NameNode, and secondary NameNode running.
More about CFS is out of the scope of this topic. You may read more about CFS on the
DataStax blog, CFS Design, at
http://www.datastax.com/dev/blog/cassandra-file-system-
design
.
