What version of Cassandra are you using? Also what command are you using to run the rebuilds? Are you using vnodes?
On 13 June 2016 at 09:01, Fabien Rousseau <fabifab...@gmail.com> wrote: > Hello, > > We've tested adding a new DC from an existing DC having 3 nodes and RF=3 > (ie all nodes have all data). > During the rebuild process, only one node of the first DC streamed data to > the 3 nodes of the second DC. > > Our goal is to minimise the time it takes to rebuild a DC and would like > to be able to stream from all nodes. > > Starting C* with debug logs, it appears that all nodes, when computing > their "streaming plan" returns the same node for all ranges. > This is probably because all nodes in DC2 have the same view of the ring. > > I understand that when bootstrapping a new node, it's preferable to stream > from the node being replaced, but when rebuilding a new DC, it should > probably select sources "randomly" (rather than always selecting the same > source for a specific range). > What do you think ? > > Best Regards, > Fabien > -- Kurt Greaves k...@instaclustr.com www.instaclustr.com
