Replica model in Cassandra vs Mongo?

All we need is an easy explanation of the problem, so here it is.

Say in Mongo we have one primary and two replica node(simple replica no sharding). Read and write request will be handled only primary node
and replica will just backup the data in case of failover.

My understanding/question about replication(not sharding) in Cassandra

Can we have only one node(say Node_1) serving read and write requests while other two simply working as replica nodes(these nodes just takes the replica request from Node_1 , no real time request from user ) like in Mongo considering replication factor as 3 ?

Per my understanding this should not be possible in cassandra, as in cassandra , replica nodes are nodes are equal peers , so it is mandatory that any of three nodes has to serve write and read request.

Is my understanding correct ?

How to solve :

I know you bored from this bug, So we are here to help you! Take a deep breath and look at the explanation of your problem. We have many solutions to this problem, But we recommend you to use the first method because it is tested & true method that will 100% work for you.

Method 1

Yes, your understanding is correct – this allows evenly distribute load between nodes & to handle more traffic.

Why would you need replicas if they just idle? If you’re afraid of inconsistent data, then just set correct consistency levels to get strong consistency…

Note: Use and implement method 1 because this method fully tested our system.
Thank you 🙂

All methods was sourced from or, is licensed under cc by-sa 2.5, cc by-sa 3.0 and cc by-sa 4.0

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