On Dec 9, 2010, at 17:39, David Boxenhorn wrote: > In other words, if you want to use QUORUM, you need to set RF>=3. > > (I know because I had exactly the same problem.)
I naively assume that if I kill either node that holds N1 (i.e. node 1 or 3), N1 will still remain on another node. Only if both fail, I actually lose data. But apparently this is not how it works... > On Thu, Dec 9, 2010 at 6:05 PM, Sylvain Lebresne <sylv...@yakaz.com> wrote: > I'ts 2 out of the number of replicas, not the number of nodes. At RF=2, you > have > 2 replicas. And since quorum is also 2 with that replication factor, > you cannot lose > a node, otherwise some query will end up as UnavailableException. > > Again, this is not related to the total number of nodes. Even with 200 > nodes, if > you use RF=2, you will have some query that fail (altough much less that what > you are probably seeing). > > On Thu, Dec 9, 2010 at 5:00 PM, Timo Nentwig <timo.nent...@toptarif.de> wrote: > > > > On Dec 9, 2010, at 16:50, Daniel Lundin wrote: > > > >> Quorum is really only useful when RF > 2, since the for a quorum to > >> succeed RF/2+1 replicas must be available. > > > > 2/2+1==2 and I killed 1 of 3, so... don't get it. > > > >> This means for RF = 2, consistency levels QUORUM and ALL yield the same > >> result. > >> > >> /d > >> > >> On Thu, Dec 9, 2010 at 4:40 PM, Timo Nentwig <timo.nent...@toptarif.de> > >> wrote: > >>> Hi! > >>> > >>> I've 3 servers running (0.7rc1) with a replication_factor of 2 and use > >>> quorum for writes. But when I shut down one of them UnavailableExceptions > >>> are thrown. Why is that? Isn't that the sense of quorum and a > >>> fault-tolerant DB that it continues with the remaining 2 nodes and > >>> redistributes the data to the broken one as soons as its up again? > >>> > >>> What may I be doing wrong? > >>> > >>> thx > >>> tcn > > > > >
