If by one-by-one you mean you want to upgrade one after the other doing a rolling restart of each node along the way, yes, that is doable and recommended. C* guarantees interoperability between minor versions, ie 2.0.x and 2.1.x in this example. Check your changes.txt file for any upgrade gotchas like new mandatory configs and the like.
What Carlos was warning you against is upgrading just one and leaving it that way for a long time. Mark On Fri, May 6, 2016 at 2:41 AM Carlos Rolo <r...@pythian.com> wrote: > Don't do that. > > In any case an upgrade between 2.0.x and 2.1.x is not so complex and > difficult to do. And it is "downtime free". I would get the opportunity to > do a full cluster upgrade. > > Regards, > > Carlos Juzarte Rolo > Cassandra Consultant / Datastax Certified Architect / Cassandra MVP > > Pythian - Love your data > > rolo@pythian | Twitter: @cjrolo | Skype: cjr2k3 | Linkedin: > *linkedin.com/in/carlosjuzarterolo > <http://linkedin.com/in/carlosjuzarterolo>* > Mobile: +351 918 918 100 > www.pythian.com > > On Thu, May 5, 2016 at 4:54 PM, Li, Guangxing <guangxing...@pearson.com> > wrote: > > > Hi, > > > > due to internal infrastructure changes, we have to replace all nodes with > > new nodes. All the existing nodes are running Cassandra Community version > > 2.0.9. I was thinking may be this is also an opportunity for us to > upgrade > > to Cassandra Community version 2.1.14. I hope I am not asking a crazy > > question: But can I replace a 2.0.9 node with a 2.1.14 node in the > cluster, > > i.e. can 2.0.9 nodes and 2.1.14 nodes work peacefully together in a > cluster > > if I replace 2.0.9 nodes with 2.1.14 nodes one by one? > > > > Thanks. > > > > George. > > > > -- > > > -- > > > >
