Thanks Dave. I've been using Cassandra, so I'm trying to get my head
around the configuration/operational differences with ZK. You state
that using 4 would actually decrease my reliability. Can you explain
that further? I was under the impression that a 4th node would act as a
non voting read only node until one of the other 3 fails. I thought
that this extra node would give me some breathing room by allowing any
node to fail and still have 3 voting nodes. Is this not the case?
On Wed, 2010-08-25 at 21:13 -0600, Ted Dunning wrote:
> Just use 3 nodes. Life will be better.
> You can configure the fourth node in the event of one of the first
> three failing and bring it on line. Then you can re-configure and
> restart each of the others one at a time. This gives you flexibility
> because you have 4 nodes, but doesn't decrease your reliability the
> way that using a four node cluster would. If you need to do
> maintenance on one node, just configure that node out as if it had
> On Wed, Aug 25, 2010 at 4:26 PM, Dave Wright <wrig...@gmail.com>
> You can certainly serve more reads with a 4th node, but I'm
> not sure
> what you mean by "it won't have a voting role". It still
> in voting for leaders as do all non-observers regardless of
> whether it
> is an even or odd number. With zookeeper there is no voting on
> transaction, only leader changes.
> -Dave Wright
> On Wed, Aug 25, 2010 at 6:22 PM, Todd Nine
> <t...@spidertracks.co.nz> wrote:
> > Do I get any read performance increase (similar to an
> observer) since
> > the node will not have a voting role?