Thanks sylvain, will look into the new stuff.
----------------- Aaron Morton Freelance Cassandra Developer @aaronmorton http://www.thelastpickle.com On 22/09/2011, at 9:09 PM, Sylvain Lebresne wrote: > 2011/9/22 Jonas Borgström <jo...@borgstrom.se>: >> On 09/22/2011 01:25 AM, aaron morton wrote: >> *snip* >>> When you start a repair it will repair will the other nodes it >>> replicates data with. So you only need to run it every RF nodes. Start >>> it one one, watch the logs to see who it talks to and then start it on >>> the first node it does not talk to. And so on. > > This is not totally true because of > https://issues.apache.org/jira/browse/CASSANDRA-2610. > Basically, doing this won't make sure the full cluster is in sync > (there is a fair > chance it will, but it's not guaranteed). > It will be true in 1.0 (though in 1.0 it will be simpler and more > efficient to just run > 'nodetool repair --partitioner-range' on every node). > > >> Is this new in 0.8 or has it always been this way? >> >> From >> http://wiki.apache.org/cassandra/Operations#Frequency_of_nodetool_repair >> >> """ >> Unless your application performs no deletes, it is vital that production >> clusters run nodetool repair periodically on all nodes in the cluster. >> """ >> >> So for a 3 node cluster using RF=3, is it sufficient to run "nodetool >> repair" on one node? > > Technically, in the 3 nodes RF=3 case, you would need to do repair on > 2 nodes to make sure the cluster has been fully repaired. But it becomes > fairly complicated to know which nodes exactly once you get more than > 3 nodes in the cluster or you have RF > 3, so to be safe I would advise > sticking to the wiki instruction (until 1.0 at least). > >> >> / Jonas >>
