For reads, is Quorum necessary? Reads are served from local the local replica, right?
On Wed, May 9, 2018 at 8:29 AM, Jordan Zimmerman <jor...@jordanzimmerman.com > wrote: > A quorum means (n/2)+1 - In a 3 node cluster that is 2. So, if 2 servers > are up you can achieve quorum. > > > we need odd > > numbers in order to form a quorum > > The "odd" in this formula refers to the number of configured servers not > how many are running at a given time. That's the reasoning for quorum in > the first place. Quorum I/O ensures that a majority of nodes is referenced > for reads or writes (in ZooKeeper writes are what matter for quorum). > > -Jordan > > > On May 9, 2018, at 10:26 AM, Kaushal Shriyan <kaushalshri...@gmail.com> > wrote: > > > > Hi, > > > > In a ensemble of 3 nodes with 1 leader and 2 followers, if the leader > goes > > down then two servers can elect a leader among themselves. But we need > odd > > numbers in order to form a quorum. I am confused. Please correct me if i > am > > understanding it wrong. > > > > Any help will be highly appreciable > > > > Best Regards, > > > > Kaushal > >
