You may do, if a node is no longer a replica for a token range. Which would be similar to reducing the RF.
nodetool cleanup is the thing to run after you have repaired to remove data a node should no longer have. Aaron On 1 Apr 2011, at 23:10, Jonathan Colby wrote: > Hi Aaron - Yes, I've read the part about changing the replication factor on > a running cluster. I've even done it without a problem. My real point of my > question was .... > >> do you now have unused replica data on the "old" replica nodes that you need >> to clean up manually? > > any insight would be appreciated. > > On Apr 1, 2011, at 1:45 PM, aaron morton wrote: > >> See the section on Replication here >> http://wiki.apache.org/cassandra/Operations#Replication It talks about how >> to change the RF and then says you can do the same when change the placement >> strategy. >> >> It can be done, but is a little messy. >> >> Depending on your setup it may also be possible to copy / move the nodes >> manually by moving sstable files. >> >> I've not done it myself, are you able to run a test ? >> >> Hope that helps. >> Aaron >> >> On 1 Apr 2011, at 02:04, Jonathan Colby wrote: >> >>> >>> From my understanding of replica copies, cassandra picks which nodes to >>> replicate the data based on replication strategy, and those same "replica >>> partner" nodes are always used according to token ring distribution. >>> >>> If you change the replication strategy, does cassandra pick new nodes to >>> replicate to? (for example if you went from simple strategy to a >>> networkTopology strategy where copies are to be sent to another datacenter) >>> >>> If so, do you now have unused replica data on the "old" replica nodes that >>> you need to clean up manually? >> >
