Hi Alain, Thank you for your answer.
I recently queried multiple times my cluster with consistency ONE and setting "myLocalDC" (withUsedHostsPerRemoteDc=1) However sometimes (not always) I got response from the node in the remote DC. All my nodes in "myLocalDC" were up and running. I was facing an data inconsistency issue. When connecting to the remote node I got empty result, while when connecting to "myLocalDC" I got the expected result back. I was expecting that since all nodes in "myLocalDC" were up and running, no attempt would have been made to the remote node. I had to solve the problem by setting consistency "LOCAL_ONE" till I repair the remote node. Or I could alternatively have set withUsedHostsPerRemoteDc=0. Kind regards, George On Wed, Jun 8, 2016 at 7:10 PM, Alain RODRIGUEZ <arodr...@gmail.com> wrote: > Hi George, > > Would that be correct? > > > I think it is actually quite the opposite :-). > > It is very well explained here: > https://docs.datastax.com/en/drivers/java/2.0/com/datastax/driver/core/policies/DCAwareRoundRobinPolicy.Builder.html#withUsedHostsPerRemoteDc-int- > > Connection is opened to the X nodes in the remote DC. But it will only be > used to indeed do a local operation as a fallback if the operation is not > using a LOCAL_* consistency level. > > Sorry I have been so long answering you. > > ----------------------- > Alain Rodriguez - al...@thelastpickle.com > France > > The Last Pickle - Apache Cassandra Consulting > http://www.thelastpickle.com > > 2016-05-20 17:54 GMT+02:00 George Sigletos <sigle...@textkernel.nl>: > >> Hello, >> >> Using withLocalDC="myLocalDC" and withUsedHostsPerRemoteDc>0 will >> guarantee that you will connect to one of the nodes in "myLocalDC", >> >> but DOES NOT guarantee that your read/write request will be acknowledged >> by a "myLocalDC" node. It may well be acknowledged by a remote DC node as >> well, even if "myLocalDC" is up and running. >> >> Would that be correct? Thank you >> >> Kind regards, >> George >> > >
