Hi, Each DC has the whole ring, each DC contains a copy of the same data. When you add replication to a new DC, all data is copied to the new DC.
Within a DC, each range of token is 'owned' by a (primary) node (and replicas if you have RF > 1). If you add/remove a node in a DC, tokens will be rearranged between all nodes within the DC only, the other DCs won't be affected. -- Jacques-Henri Berthemet -----Original Message----- From: Jinhua Luo [mailto:luajit...@gmail.com] Sent: Wednesday, April 11, 2018 12:35 PM To: user@cassandra.apache.org Subject: does c* 3.0 use one ring for all datacenters? Hi All, I know it seems a stupid question, but I am really confused about the documents on the internet related to this topic, especially it seems that it has different answers for c* with vnodes or not. Let's assume the token range is 1-100 for the whole cluster, how does it distributed into the datacenters? Think that the number of datacenters is dynamic in a cluster, if there is only one ring, then the token range would change on each node when I add a new datacenter into the cluster? Then it would involve data migration? It doesn't make sense. Looking forward to clarification for c* 3.0, thanks! --------------------------------------------------------------------- To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org For additional commands, e-mail: user-h...@cassandra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org For additional commands, e-mail: user-h...@cassandra.apache.org
