Re: Help to understand a strange behavior with DCQUORUM

2010-05-29 Thread Jonathan Ellis
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 Echagüe patric...@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


Help to understand a strange behavior with DCQUORUM

2010-05-28 Thread Patricio Echagüe
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.-