Datacenter replication is defined in the keyspace schema, so I believe that ... WITH replication = {'class': 'NetworkTopologyStrategy', 'DC1': 1, 'DC2': 1} ... you ought to be able to repair DC1 from DC2, once you have the DC1 node healthy again.
If using the SimpleStrategy replication class, it appears that replication_factor is the only option, which applies to the entire cluster, so only one node in both datacenters would have the data. https://cassandra.apache.org/doc/latest/cql/ddl.html#create-keyspace -- Kind regards, Michael On 07/20/2017 03:23 PM, Roger Warner wrote: > Hi > > > > I’m a little dim on what multi datacenter implies in the 1 replica > case. I know about replica recovery, how about “node recovery” > > > > As I understand if there a node failure or disk crash with a single node > cluster with replication factor 1 I lose data. Easy. > > > > nodetool tells me each node in my 3 node X 2 datacenters is responsible > for ~1/3 of the data. If in this cluster with RF=1 a node fails in > dc1 what happens ? in 1 dc with data loss can the node be “restored” > from a node in dc2?. Automatically? > > > > I’m also asking tangentially how does the data map from nodes in dc1 to > dc2. > > > > I hope I made that coherent. > > > > Roger > --------------------------------------------------------------------- To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org For additional commands, e-mail: user-h...@cassandra.apache.org