when using rack aware, RF=3, W=QUORUM ... does a write block until response from both data centers? and if so is there a setting to make the write to the "second" data center async?
On Thu, 2010-02-11 at 12:12 -0800, Jonathan Ellis wrote: > 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
