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From Patricio Echag├╝e <patric...@gmail.com>
Subject Help to understand a strange behavior with DCQUORUM
Date Fri, 28 May 2010 19:15:03 GMT
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.-

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