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From aaron morton <aa...@thelastpickle.com>
Subject Re: ConsistencyLevel and write availability
Date Thu, 02 Jun 2011 05:00:46 GMT
It depends on which nodes are down and which keys you are writing. 

e.g. Using a the SimplePlacementStrategy, with the nodes ordered 0 to 9 and CL ALL. If nodes
8 and 9 are down, the cluster will still be up for all key ranges assigned to nodes 0, 1,
2 and 3 and the replicas for those ranges are stored on nodes 0,1,2,3,4,5,6,7

Token ranges assigned to nodes 4,5,6,7,8,9 will not available at CL all as nodes 8 and 9 are
part of the replica sets for those ranges. 

Cheers

-----------------
Aaron Morton
Freelance Cassandra Developer
@aaronmorton
http://www.thelastpickle.com

On 1 Jun 2011, at 01:01, Watanabe Maki wrote:

> You can write if you use CL=QUORUM, but can't write with CL=ALL.
> 
> maki
> 
> 
> On 2011/05/31, at 21:03, Flavio Baronti <f.baronti@list-group.com> wrote:
> 
>> Suppose i have a cluster with 10 nodes and RF=5.
>> Will every write succeed if one or two of my nodes are down, and I use ConsistencyLevel=ALL?
Or will some of the writes fail?


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