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The "StorageConfiguration" page has been changed by tuxracer69.
http://wiki.apache.org/cassandra/StorageConfiguration?action=diff&rev1=7&rev2=8

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  <EndPointSnitch>org.apache.cassandra.locator.EndPointSnitch</EndPointSnitch>
  }}}
  
+ Note: this class will work on hosts' IPs only. There is no configuration 
parameter to tell Cassandra that a node is in rack ''R'' and in datacenter 
''D''. The current rules are based on the two methods: (see 
[[http://svn.apache.org/viewvc/incubator/cassandra/trunk/src/java/org/apache/cassandra/locator/EndPointSnitch.java?view=markup|EndPointSnitch.java]]):
+ 
+  * isOnSameRack: Look at the IP Address of the two hosts. Compare the 3rd 
octet. If they are the same then the hosts are in the same rack else different 
racks. 
+ 
+  * isInSameDataCenter: Look at the IP Address of the two hosts. Compare the 
2nd octet. If they are the same then the hosts are in the same datacenter else 
different datacenter. 
+ 
  == ReplicaPlacementStrategy ==
  Strategy: Setting this to the class that implements 
{{{IReplicaPlacementStrategy}}} will change the way the node picker works. Out 
of the box, Cassandra provides 
{{{org.apache.cassandra.locator.RackUnawareStrategy}}} and 
{{{org.apache.cassandra.locator.RackAwareStrategy}}} (place one replica in a 
different datacenter, and the others on different racks in the same one.)
  

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