On 8/7/2013 2:45 PM, Torsten Albrecht wrote:
I would like to run zookeeper external at my old master server.
So I have two zookeeper to control my cloud. The third and fourth zookeeper
will be a virtual machine.
For true HA with zookepeer, you need at least three instances on
separate physical hardware. If you want to use VMs, that would be fine,
but you must ensure that you aren't running more than one instance on
the same physical server.
For best results, use an odd number of ZK instances. With three ZK
instances, one can go down and everything still works. With five, two
can go down and everything still works.
If you've got a fully switched network that's at least gigabit speed,
then the network latency involved in internal communication shouldn't
really matter.
Thanks,
Shawn