On Thu, Aug 7, 2014 at 2:46 PM, Viswanathan Ramachandran < [email protected]> wrote:
> I plan to have a multi data center Cassandra 2 setup with 2-4 nodes per > data center and several 10s of data centers. We have My understanding is > that nodetool cleanup removes data which no longer belongs to that node. > When a new data center is being setup, we are creating completely new > replicas and AFAICT, it does not result in data movement/rebalance outside > of this new data center and hence there is no cleanup requirement on nodes > of other data centers. Is someone able to confirm if my understanding is > right, and cleanup is not required on nodes of other data centers? > This is the correct understanding; as you say, the key is that cleanup removes data which no longer belongs to a node. In this situation, no node loses responsibility for any replica, so cleanup is not necessary. For what it's worth, 2-4 nodes per data center and several 10s of data centers is an unusual deploy for Cassandra. If you can discuss it, what is the use case? =Rob
