We have a ring (10 nodes in 2 datacenters) running Cassandra 0.7.9. We are replacing the nodes with 10 new nodes and would like to upgrade to Datastax Community 1.1.2 in the process. What's the best upgrade approach? Is it as simple as adding the new nodes to the cluster, then slowly removing the old nodes? During this migration we'd also like to upgrade the OS to CentOS 6.2 (from 5.4).
Thanks for any help or pointers.