DataStax Academy FAQ

DataStax Academy migrated to a new learning management system (LMS) in July 2020. We are also moving to a new Cassandra Certification process so there are changes to exam bookings, voucher system and issuing of certificates.

Check out the Academy FAQ pages for answers to your questions:


question

Aravind Palani avatar image
Aravind Palani asked ·

How does replication factor widen the token range and what will cause it to overlap?

Replication factor of 2 will widen the token range assignment of node? And what is token range overlap?

cassandrareplication
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1 Answer

bettina.swynnerton avatar image
bettina.swynnerton answered ·

Hi,

Before a node can join a Cassandra ring, it must be assigned a token. The token value determines the node's position in the ring and its token range. The token or the range are independent of the replication strategies that you might define for your data.

So, to answer your question, a replication factor greater than one will not modify the token range. The token ranges generally don't change unless you add or remove nodes from the ring.

Token ranges will also not overlap. Each token belongs to one range and one node only.

The replication strategy and replication factor determine which nodes will store a replica of the data. For example, SimpleStrategy places the first replica on a node determined by the token. Additional replicas are placed on the next nodes in the ring.

I hope this helps!

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