> Could you provide some guide on how to assign the tokens in this growing > deployment phases?
background http://www.datastax.com/docs/1.0/install/cluster_init#calculating-tokens-for-a-multi-data-center-cluster Start with tokens for a 4 node cluster. Add the next 4 between between each of the ranges. Add 8 in the new DC to have the same tokens as the first DC +1 > Also if we use the same RF (3) in both DC, and use EACH_QUORUM for write and > LOCAL_QUORUM for read, can the read also reach to the 2nd cluster? No. It will fail if there are not enough nodes available in the first DC. > We'd like to keep both write and read on the same cluster. Writes go to all replicas. Using EACH_QUORUM means the client in the first DC will be waiting for the quorum from the second DC to ack the write. Cheers ----------------- Aaron Morton Freelance Developer @aaronmorton http://www.thelastpickle.com On 31/05/2012, at 3:20 AM, Chong Zhang wrote: > Hi all, > > We are planning to deploy a small cluster with 4 nodes in one DC first, and > will expend that to 8 nodes, then add another DC with 8 nodes for fail over > (not active-active), so all the traffic will go to the 1st cluster, and > switch to 2nd cluster if the whole 1st cluster is down or on maintenance. > > Could you provide some guide on how to assign the tokens in this growing > deployment phases? I looked at some docs but not very clear on how to assign > tokens on the fail-over case. > Also if we use the same RF (3) in both DC, and use EACH_QUORUM for write and > LOCAL_QUORUM for read, can the read also reach to the 2nd cluster? We'd like > to keep both write and read on the same cluster. > > Thanks in advance, > Chong
