> More exactly, if you write a record in a node in DC1 will it send one replica > of it to DC2 and then another replica to DC3? Or will the node in DC2 > replicate the record to DC3 in a chain effect? Coordinator in DC 1 will send the mutation to both DC2 and DC3 at the same time.
> I need to understand this because the connection between DC1 and DC2/DC3 is > limited and ideally I would only want to send a replica to DC2 and have DC2 > send a replicat to DC3. Is this possible? No. That would tie the availability if DC 3 directly to DC 2. Cheers ----------------- Aaron Morton Freelance Developer @aaronmorton http://www.thelastpickle.com On 20/03/2012, at 9:50 AM, Alexandru Sicoe wrote: > Hi everyone, > > If you have 3 data centers (DC1,DC2 and DC3) with 3 nodes each and you have a > keyspace where the strategy options are such that each DC gets 2 replicas. If > you only write to the nodes in DC1 what is the path the replicas take? > Assuming you've correctly interleaved the tokens of all the nodes [(DC1: > x,y,z), (DC2:x+1,y+1,z+1), (DC3:x+2,y+2,z+2)]? > > More exactly, if you write a record in a node in DC1 will it send one replica > of it to DC2 and then another replica to DC3? Or will the node in DC2 > replicate the record to DC3 in a chain effect? > > I understand that each DC handles it's own internal replication (after a node > receives one replica). > > I need to understand this because the connection between DC1 and DC2/DC3 is > limited and ideally I would only want to send a replica to DC2 and have DC2 > send a replicat to DC3. Is this possible? > > Cheers, > Alex
