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From Brandon Williams <dri...@gmail.com>
Subject Re: Local quorum reads
Date Sat, 19 Nov 2011 01:55:48 GMT
On Fri, Nov 18, 2011 at 4:23 PM, Anthony Ikeda
<anthony.ikeda.dev@gmail.com> wrote:
> This is the setup:
> Cassandra 0.8.6
> 3 nodes
> Keyspace: NetworkTopologyStrategy, 1DC, RF=2
>
> 1 node goes down and we cannot read from the ring.
>
> My expectation is that LOCAL_QUORUM dictates that it will return a record once a majority
(N/2 +1) of replicas reports back.
>
> 2/2 + 1 = 2
>
> I originally thought N=3 for 3 nodes but someone has corrected me on this that it's the
replicas (2) but when I use the cli, setConsistencyLevel AS LOCAL_QUORUM nothing comes back.
Set it back to ONE I can see the data
>
> Is there somethin I'm missing?

You've arrived at the right answer, 2, but you're using N to refer to
the amount of nodes (in the last part), where you need it to refer to
the RF.  RF=3 is the minimum amount where you can achieve quorum with
a member of the replica set being down.

-Brandon

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