What does adding nodes in Cassandra generally means?

Question

Hi I have a cassandra DB with a huge amount of data and I am using only one node to store it.So someone suggested me to use multiple nodes .

So what will happen if I add a new node , will the data get replicated to the other node or it will distributed equally with the other node ?

I am new to cassandra and DB management. It would help if some can share some thoughts regarding this ...It would be very helpful

Answer 1

will the data get replicated to the other node or it will distributed equally with the other node ?

Both. Data will get replicated to other nodes depending on the replication strategy and replication factor for each keyspace. But data will also be split across nodes to balance the load. A new node that joins the cluster assumes responsibility for an even portion of the data automatically.

P.S. I'd advise you to run [nodetool cleanup] on the old nodes (http://www.datastax.com/documentation/cassandra/2.0/cassandra/operations/ops_add_node_to_cluster_t.html) post adding the new nodes. This will help cleanup keys that no longer belong to the old nodes