On 18 January 2011 07:15, Samuel Benz <samuel.b...@switch.ch> wrote: > On 01/17/2011 09:28 PM, Jonathan Ellis wrote: >> On Mon, Jan 17, 2011 at 2:10 PM, Samuel Benz <samuel.b...@switch.ch> wrote: >>>>> Case1: >>>>> If 'TEST' was previous stored on Node1, Node2, Node3 -> The update will >>>>> succeed. >>>>> >>>>> Case2: >>>>> If 'TEST' was previous stored on Node2, Node3, Node4 -> The update will >>>>> not work. >>>> >>>> If you have RF=2 then it will be stored on 2 nodes, not 3. I think >>>> this is the source of the confusion. >>>> >>> >>> I checked the existence of the row on the different serverver with >>> sstablekeys after flushing. So I saw three copies of every key in the >>> cluster. >> >> If you want to be guaranteed to be able to read with two nodes down >> and RF=3, you have to read at CL.ONE, since if the two nodes that are >> down are replicas of the data you are reading (as in the 2nd case >> here) Cassandra will be unable to achieve quorum (quorum of 3 is 2 >> live nodes). >> > > Now it seems clear to me. Thanks! > > I was confused by the fact that: "live nodes" != "replica live nodes" > > Correct me if I'm wrong, but even in a cluster with 1000 nodes and RF=3, > if I shut down the wrong two nodes, i have the same problem as in my > mini cluster.
Correct > > > -- > Sam >
