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From David Schairer <dschai...@humbaba.net>
Subject Re: Multiple data center nodetool ring output display 0% owns
Date Mon, 13 Feb 2012 02:09:00 GMT
There was a thread on this a couple days ago -- short answer, the 'owns %' column is effectively
incorrect when you're using multiple DCs.  If you had all 3 servers in 1 DC, since server
YYY has token 1 and server XXX has token 0, then server XXX would truly 'own' 0% (actually,
1/(2^128) :) ), and depending on your replication factor might have no data (if replication
were 1).  

But two data centers is effectively like two rings - since the two nodes in DC2 are token-balanced,
you'd see even distribution between them, and DC1 has only one server, so that would be even
as well (assuming you replicate to both sites).

--DRS

On Feb 12, 2012, at 5:42 PM, Roshan wrote:

> Hi
> 
> I have deployed Cassandra 1.0.6 to a 2 data center and one data center (DC1)
> having one node and the other data center (DC2) having two nodes. But when I
> do a nodetool ring using one IP, the output says 0% owns of DC1 node. Please
> see the output below.
> 
> # sh nodetool -h 10.XXX.XXX.XX ring
> Address         DC          Rack        Status State   Load            Owns   
> Token                                       
> 
> 85070591730234615865843651857942052864      
> XXX.XXX.XXX.XXX DC2         RAC1        Up     Normal  83.89 KB       
> 50.00%  0                                           
> YYY.YYY.YY.YYY  DC1         RAC1        Up     Normal  71.4 KB         0.00%  
> 1                                           
> ZZ.ZZZ.ZZZ.ZZ   DC2         RAC1        Up     Normal  65.94 KB       
> 50.00%  85070591730234615865843651857942052864 
> 
> Could someone explain this behavior.      
> 
> --
> View this message in context: http://cassandra-user-incubator-apache-org.3065146.n2.nabble.com/Multiple-data-center-nodetool-ring-output-display-0-owns-tp7279122p7279122.html
> Sent from the cassandra-user@incubator.apache.org mailing list archive at Nabble.com.


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