Thanks, Aaron. Moving one node at a time and running repair does seem to do the trick.
Bill On Thu, May 10, 2012 at 7:03 AM, aaron morton <aa...@thelastpickle.com>wrote: > That's a bit tricky. How many nodes, what is the replication and what is > the current rack assignment ? > > NTS stripes data over the racks in a DC, looping around until the RF is > reached. If you change the rack assignments there is a chance data will be > lost. Or at least go missing until a repair or reap repair puts it in the > right place. > > The logic is something like: > 1) For each DC get all the nodes. > 2) Order the nodes in the DC by token. > 3) For each node in the DC get the rack, if the rack has not been seen > before make the node a replica. Stop when the RF is reached. > 4) If the RF for the DC is not reached, iterate over the sorted nodes in > the DC and make them replicas if they have not been seen before. (Does not > check rack again.) > > You should be able to move one node at a time and run repair. Also ensure > reads are at QUOURM. > > hope that helps. > > ----------------- > Aaron Morton > Freelance Developer > @aaronmorton > http://www.thelastpickle.com > > On 10/05/2012, at 2:08 AM, Bill Au wrote: > > I am running 1.0.8 with NetworkTopologyStrategy and need to change the > rack assignment of my nodes. How do I get Cassandra to re-distribute the > existing replica according to the new rack assignment? Will nodetool > repair do the trick? > > Bill > > >
