See the section on Moving or Removing nodes here http://wiki.apache.org/cassandra/Operations you should also read the bootstrapping section as that is essentially what you are doing.
AFAIK you should use nodetool move to assign a new token to the nodes. As you say, loadbalance is not recommended. The token for the node represents the end of it's token range, i.e. it's responsible for the data from the previous nodes token to it's. My guess of the best approach would be... I'm think most of your keys are in the range managed by the 15 node. As the 128 node has the same load and a much smaller key range. Use get_range_slices to have a look at the keys in your db, or use your knowledge of the keys you are generating. You need to understand if you are making lots of keys that start with "aaaa". It may help if you provide some more info on the keys. If it is true that all the keys fall between wpt0w4Aomuhb8MQh and jnGTn7PwLTh6dxmC I would move the 155 node to have a token that is about two thirds of the keys between those tokens. Then move the 239 node to have a token that is one third of the keys. I'd let each node move complete first, watch the streams to see when it's done. Then when finished and everything is working, run nodetool cleanup on each node. I've not actually done this before, I just wanted to think about the problem :) So I'd also wait for one of the adults around here to weigh in. Aaron On 11 Sep 2010, at 19:53, maneela a wrote: > we have a Cassandra set up running with 4 nodes with Reflicationfactor:2 and > OrderPreservingPartitioner as partitioner but we have not provided > InitialToken values. > > Could some one suggest me what is best way to balance my cluster because some > of user threads have suggested "do not ever run nodetool loadbalance" option. > which node I should start running loadbalance command first before doing on > 2nd node if that option suits for my scenario. > > > r...@ip-10-251-190-239:/etc/cassandra# nodetool -h localhost ring > Address Status Load Range > Ring > wpt0w4Aomuhb8MQh > > 10.202.87.15 Up 119.4 GB jnGTn7PwLTh6dxmC > |<--| > 10.223.71.128 Up 119.82 GB kopMmFKwbk1yZFNX > | | > 10.251.190.239Up 2.56 KB v8w434UBnDIJyrIe > | | > 10.201.217.155Up 2.56 KB wpt0w4Aomuhb8MQh > |-->| > r...@ip-10-251-190-239:/etc/cassandra# > >
