@jeff, I'm using 3 availability zones, during the life of the cluster we lost nodes, retired others and we end up having some of the data written/replicated on a single availability zone. We saw it with nodetool getendpoints. Regards
>Thursday, September 14, 2017 9:23 AM -07:00 from Jeff Jirsa <jji...@gmail.com>: > >With one datacenter/region, what did you discover in an outage you think >you'll solve with network topology strategy? It should be equivalent for a >single D.C. > >-- >Jeff Jirsa > > >On Sep 14, 2017, at 8:47 AM, Dominik Petrovic < >dominik.petro...@mail.ru.INVALID > wrote: > >>Thank you for the replies! >> >>@jeff my current cluster details are: >>1 datacenter >>40 nodes, with vnodes=256 >>RF=3 >>What is your advice? is it a production cluster, so I need to be very careful >>about it. >>Regards >> >> >>>Thu, 14 Sep 2017 -2:47:52 -0700 from Jeff Jirsa < jji...@gmail.com >: >>> >>>The token distribution isn't going to change - the way Cassandra maps >>>replicas will change. >>> >>>How many data centers/regions will you have when you're done? What's your RF >>>now? You definitely need to run repair before you ALTER, but you've got a >>>bit of a race here between the repairs and the ALTER, which you MAY be able >>>to work around if we know more about your cluster. >>> >>>How many nodes >>>How many regions >>>How many replicas per region when you're done? >>> >>> >>> >>> >>>-- >>>Jeff Jirsa >>> >>> >>>On Sep 13, 2017, at 2:04 PM, Dominik Petrovic < >>>dominik.petro...@mail.ru.INVALID > wrote: >>> >>>>Dear community, >>>>I'd like to receive additional info on how to modify a keyspace replication >>>>strategy. >>>> >>>>My Cassandra cluster is on AWS, Cassandra 2.1.15 using vnodes, the >>>>cluster's snitch is configured to Ec2Snitch, but the keyspace the >>>>developers created has replication class SimpleStrategy = 3. >>>> >>>>During an outage last week we realized the discrepancy between the >>>>configuration and we would now fix the issue using NetworkTopologyStrategy. >>>> >>>>What are the suggested steps to perform? >>>>For Cassandra 2.1 I found only this doc: >>>>http://docs.datastax.com/en/cassandra/2.1/cassandra/operations/opsChangeKSStrategy.html >>>> >>>>that does not mention anything about repairing the cluster >>>> >>>>For Cassandra 3 I found this other doc: >>>>https://docs.datastax.com/en/cassandra/3.0/cassandra/operations/opsChangeKSStrategy.html >>>> >>>>That involves also the cluster repair operation. >>>> >>>>On a test cluster I tried the steps for Cassandra 2.1 but the token >>>>distribution in the ring didn't change so I'm assuming that wasn't the >>>>right think to do. >>>>I also perform a nodetool repair -pr but nothing changed as well. >>>>Some advice? >>>> >>>>-- >>>>Dominik Petrovic >> >>-- >>Dominik Petrovic -- Dominik Petrovic
