What is the minimum number of nodes required to form a cassanadra cluster ?
* EDIT : (i.e. Recommended / Best practice)
Hi Wale,
It is possible to have a one node Cassandra Cluster, so the minimum would be one. Keep in mind that this means that you have a single point of failure (if that one node is down or does not respond, you can see problems in DataMiner). For more details on what data storage options are supported: Supported System Data Storage Architectures - DataMiner Dojo
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@Michiel, I guess the best practice would then be to have at least 3 nodes and a replication factor of at least 2?
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The best practice would be to start with 3 nodes and RF 3 IMO. Then you have 3 copies of all data, so if one node goes down you still have a majority of nodes available. You can use a CL (consistency level) Quorum to ensure consistent data and cope with one node going down from RF3. For the tables that you deem less important (e.g. real-time trending), you could use a lower CL or even reduce the RF to reduce the resources needed for your system load.
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Thanks for bringing that up Ive. What I really wanted to know was the recommended minimum number of of nodes.
Note: For Elastic if you want to have redundancy you need at least 3 nodes (master nodes) as using 2 master nodes is not supported.