No it wont.... it will assume you are doing the right thing... Regards, </VJ>
On Wed, Jun 15, 2011 at 2:34 PM, AJ <a...@dude.podzone.net> wrote: > Vijay, thank you for your thoughtful reply. Will Cass complain if I don't > setup my tokens like in the examples? > > > On 6/15/2011 2:41 PM, Vijay wrote: > > All you heard is right... > You are not overriding Cassandra's token assignment by saying here is your > token... > > Logic is: > Calculate a token for the given key... > find the node in each region independently (If you use NTS and if you set > the strategy options which says you want to replicate to the other > region)... > Search for the ranges in each region independntly > Replicate the data to that node. > > For multi DC cassandra needs nodes to be equally partitioned within each > dc (If you care that the load equally distributed).... as well as > there shouldn't be any collusion of tokens within a cluster.... > > The documentation tried to explain the same and the example in the > documentation. > Hope this clarifies... > > More examples if it helps.... > > DC1 Node 1 : token 0 > DC1 Node 2 : token 8.. > > DC2 Node 1 : token 4.. > DC2 Node 1 : token 12.. > > or > > DC1 Node 1 : token 0 > DC1 Node 2 : token 1.. > > DC2 Node 1 : token 8.. > DC2 Node 1 : token 7.. > > Regards, > </VJ> > > > > On Wed, Jun 15, 2011 at 12:28 PM, AJ <a...@dude.podzone.net> wrote: > >> On 6/15/2011 12:14 PM, Vijay wrote: >> >> Correction.... >> >> "The problem in the above approach is you have 2 nodes between 12 to 4 >> in DC1 but from 4 to 12 you just have 1" >> >> should be >> >> "The problem in the above approach is you have 1 node between 0-4 (25%) >> and and one node covering the rest which is 4-16, 0-0 (75%)" >> >> Regards, >> </VJ> >> >> >> Ok, I think you are saying that the computed token range intervals are >> incorrect and that they would be: >> >> DC1 >> *node 1 = 0 Range: (4, 16], (0, 0] >> >> node 2 = 4 Range: (0, 4] >> >> DC2 >> *node 3 = 8 Range: (12, 16], (0, 8] >> >> node 4 = 12 Range: (8, 12] >> >> If so, then yes, this is what I am seeking to confirm since I haven't >> found any documentation stating this directly and that reference that I gave >> only implies this; that is, that the token ranges are calculated per data >> center rather than per cluster. I just need someone to confirm that 100% >> because it doesn't sound right to me based on everything else I've read. >> >> SO, the question is: Does Cass calculate the consecutive node token >> ranges A.) per cluster, or B.) for the whole data center? >> >> From all I understand, the answer is B. But, that documentation >> (reprinted below) implies A... or something that doesn't make sense to me >> because of the token placement in the example: >> >> "With NetworkTopologyStrategy, you should calculate the tokens the nodes >> in each DC independantly... >> >> DC1 >> node 1 = 0 >> node 2 = 85070591730234615865843651857942052864 >> >> DC2 >> node 3 = 1 >> node 4 = 850705917302346158658436518579 >> 42052865" >> >> >> However, I do see why this would be helpful, but first I'm just asking if >> this token assignment is absolutely mandatory >> or if it's just a technique to achieve some end. >> >> >> >> > >
