With 3 nodes and RF=2 you have 3 key ranges: N1+N2, N2+N3 and N3+N1. Killing N1 you've got only 1 alive range N2+N3 and 2/3 of the range is down for Quorum, which is actually all, so N1+N2 and N3+N1 fails.
-----Original Message----- From: Timo Nentwig [mailto:timo.nent...@toptarif.de] Sent: Thursday, December 09, 2010 6:01 PM To: user@cassandra.apache.org Subject: Re: Quorum: killing 1 out of 3 server kills the cluster (?) 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
