The definitive guide specifically advises against having a cluster spanning more than one data center, and certainly not across continents.
What then is the best architecture for solutions that use elasticsearch and do span continents?
Let's say for performance and high-availability reasons that you have three clusters of webservers in US, Europe, and Asia. These webservers use elasticseach.
Is the only viable option then to just have all the elasticsearch servers in one of the above sites?