Cassandra NoHostAvailable: Error In CQLSH


Answer :

This is too late to answer. But I wanted to share my experience.

If you have a single node cluster and use NetworkTopologyStrategy, then it throws this error. Check your keyspace configuration.

Error during inserting data: NoHostAvailable:


My CQL command to update the replication 

ALTER KEYSPACE my_keyspace WITH replication = {'class' : 'NetworkTopologyStrategy', 'DC1' : 1 ,'DC2' :2 };

was slightly different from the config files : conf/cassandra-rackdc.properties

# These properties are used with GossipingPropertyFileSnitch and will # indicate the rack and dc for this node dc=dc1 rack=rack1

resulting in a 

cqlsh: my_keyspace> select * from world where message_id = 'hello_world';

NoHostAvailable:

the replication strategy is case sensitive and copy/paste from documentation may lead you to a mistake.

Fix : Changing the replication info so that it match the config files 

ALTER KEYSPACE my_keyspace WITH replication = {'class' : 'NetworkTopologyStrategy', 'dc1' : 1 ,'dc2' :2 };

And execute on each node :

bin/nodetool repair --full my_keyspace

Got replication set on every node


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