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From Samuel Benz <>
Subject Re: quorum calculation seems to depend on previous selected nodes
Date Mon, 17 Jan 2011 20:10:06 GMT
On 01/17/2011 05:08 PM, Jonathan Ellis wrote:
> On Mon, Jan 17, 2011 at 9:55 AM, Samuel Benz <> wrote:
>> We have a cluster with 4 nodes. ReplicationFactor is 2, ReplicaPlacment
>> is the RackAwareStrategy and the EndpointSnitch is the
>> PropertyFileEndpointSnitch (with two data center and two racks each).
>> My understanding is, that with this parameter of the cluster, it should
>> be possible to update with consistency level quorum while one data
>> center (two nodes) are shutdown completely.
> No.  Quorum of 2 is 2.

I made a big mistake in my Email! Sorry for the confusion. Of course the
ReplicationFactor of the cluster is 3! (but the rest of the email is

>> 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


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