Sorry, i meant 5 nodes in previous question.
On Tue, Jun 24, 2014 at 12:36 PM, Kane Kane <kane.ist...@gmail.com> wrote: > Hello Neha, > >>>ZK cluster of 3 nodes will tolerate the loss of 1 node, but if there is a > subsequent leader election for any reason, there is a chance that the > cluster does not reach a quorum. It is less likely but still risky to some > extent. > > Does it mean if you have to tolerate 1 node loss without any issues, > you need *at least* 4 nodes? > > On Tue, Jun 24, 2014 at 11:16 AM, Neha Narkhede <neha.narkh...@gmail.com> > wrote: >> Can you elaborate your notion of "smooth"? I thought if you have >> replication factor=3 in this case, you should be able to tolerate loss >> of a node? >> >> Yes, you should be able to tolerate the loss of a node but if controlled >> shutdown is not enabled, the delay between loss of the old leader and >> election of the new leader will be longer. >> >> So, you mean ZK cluster of 3 nodes can't tolerate 1 node loss? I've >> seen many recommendations to run 3-nodes cluster, does it mean in >> cluster of 3 you won't be able to operate after loosing 1 node? >> >> ZK cluster of 3 nodes will tolerate the loss of 1 node, but if there is a >> subsequent leader election for any reason, there is a chance that the >> cluster does not reach a quorum. It is less likely but still risky to some >> extent. >> >> >> On Tue, Jun 24, 2014 at 2:44 AM, Hemath Kumar <hksrckmur...@gmail.com> >> wrote: >> >>> Yes kane i have the replication factor configured as 3 >>> >>> >>> On Tue, Jun 24, 2014 at 2:42 AM, Kane Kane <kane.ist...@gmail.com> wrote: >>> >>> > Hello Neha, can you explain your statements: >>> > >>Bringing one node down in a cluster will go smoothly only if your >>> > replication factor is 1 and you enabled controlled shutdown on the >>> brokers. >>> > >>> > Can you elaborate your notion of "smooth"? I thought if you have >>> > replication factor=3 in this case, you should be able to tolerate loss >>> > of a node? >>> > >>> > >>Also, bringing down 1 node our of a 3 node zookeeper cluster is risky, >>> > since any subsequent leader election might not reach a quorum. >>> > >>> > So, you mean ZK cluster of 3 nodes can't tolerate 1 node loss? I've >>> > seen many recommendations to run 3-nodes cluster, does it mean in >>> > cluster of 3 you won't be able to operate after loosing 1 node? >>> > >>> > Thanks. >>> > >>> > On Mon, Jun 23, 2014 at 9:04 AM, Neha Narkhede <neha.narkh...@gmail.com> >>> > wrote: >>> > > Bringing one node down in a cluster will go smoothly only if your >>> > > replication factor is 1 and you enabled controlled shutdown on the >>> > brokers. >>> > > Also, bringing down 1 node our of a 3 node zookeeper cluster is risky, >>> > > since any subsequent leader election might not reach a quorum. Having >>> > said >>> > > that, a partition going offline shouldn't cause a consumer's offset to >>> > > reset to an old value. How did you find out what the consumer's offset >>> > was? >>> > > Do you have your consumer's logs around? >>> > > >>> > > Thanks, >>> > > Neha >>> > > >>> > > >>> > > On Mon, Jun 23, 2014 at 12:28 AM, Hemath Kumar <hksrckmur...@gmail.com >>> > >>> > > wrote: >>> > > >>> > >> We have a 3 node cluster ( 3 kafka + 3 ZK nodes ) . Recently we came >>> > across >>> > >> a strange issue where we wanted to bring one of the node down from >>> > cluster >>> > >> ( 1 kafka + 1 zookeeper) for doing a maintenance . But the movement we >>> > >> brought it to down on some of the topics ( only some partitions) >>> > consumers >>> > >> offset is reset some old value. >>> > >> >>> > >> Any reason why this is happened?. As of my knowledge when brought one >>> > node >>> > >> down its should work smoothly with out any impact. >>> > >> >>> > >> Thanks, >>> > >> Murthy Chelankuri >>> > >> >>> > >>>
