I'm prototyping a solution using ZooKeeper that relies on geographic
redundancy. Specifically, we require two geographically redundant sites,
but I'm not sure how this should be configured with ZooKeepers quorum
requirements. The number of clients and amount of data being written and
consumed will be quite small (in terms of what ZooKeeper can handle), so
from capacity point of view we can get away with 3 ZK nodes.
How should these be configured though to achieve geographical redundancy?
We can't just have 2 ZK nodes at one site and 1 at the other, as this means
that if the site with 2 nodes explodes then the other site cannot take over.
The only way I can think of achieving this redundancy is by having 3 sites,
each with a single ZK node. This is not ideal though as it means that we
need another site purely for ZK.
Am I missing something here?