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From Jonathan Ellis <jbel...@gmail.com>
Subject Re: Help to understand a strange behavior with DCQUORUM
Date Sat, 29 May 2010 12:03:27 GMT
DCQUORUM is not finished in 0.6, which is why it's not documented
there.  If you want to test it you'll need to live on the bleeding
edge of trunk (or wait for a 0.7 beta).

2010/5/28 Patricio Echag├╝e <patricioe@gmail.com>:
> Hi all, I need to help to understand how DCQUORUM works.
>
> This is my setup:
>
> - Cluster with 3 Cassandra Nodes
> - RF = 3
> - ReplicatePlacementStrategy = RackUnawareStrategy
>
> My test:
> - I write/read with DCQUORUM
>
> Results:
> - While the 3 nodes are UP, all my writes and read succeed. (the nodes are
> reached, and the third one -to complete the RF=3- is done my replication,
> right?)
> - When I killed one node, the test FAILED with UnavailableException
> - When I performed the same test but with QUORUM instead of DCQUORUM, It
> succeeded.
>
> Could someone explain please why reads and writes with DCQUORUM worked fine
> while the 3 nodes were up and running but failed when 1 was down even thouch
> I have only one Data Center?
>
> Thanks in advance
>
> --
> Patricio.-
>



-- 
Jonathan Ellis
Project Chair, Apache Cassandra
co-founder of Riptano, the source for professional Cassandra support
http://riptano.com

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