On Thu, Feb 11, 2010 at 1:53 PM, Weijun Li <weiju...@gmail.com> wrote: > Hello, > > I have a testing cluster with: A (dc1), B (dc1), C(dc2), D(dc2). The > replication factor is 2 so I assume each DC will have a complete copy of the > data. Also I'm using PropertyFileEndPointSnitch with rack.properties for the > dc and rack settings. > > So, what's the steps to add another datacenter and increase replication > factor to 3 to ensure that dc3 will also get a complete copy of the data?
RackAwareStrategy only cares about replicating to 2 datacenters out of Y. So (1) Write a ReplicationStrategy that extends RAS's algorithm to replicating to Y of Y DCs (1a) alternatively, make RAS configurable to be X of Y where X could be 2 (current) or Y (your case) or anything in between (2) deploy the new RS, bring up nodes in your 3rd DC, and repair them. -Jonathan
