e72bfd15_Cassandra_vs_HBase___WhyNosql__Cassandra
[HBase] Although there exists a concept of a master server, HBase itself does not depend on it heavily. HBase cluster can keep serving data even if the master goes down. Hadoop namenode is a single point of failure. [Cassandra] 
No master server, hence no single point of failure.
Cassandra vs HBase | WhyNosql
Cassandra