Having multiple datacenters worldwide is a key feature for a cloud service provider because it gives to the customer the possibility to instantiate the services near the users, lowering latency time. Also, having a similar system is necessary for CDN providers.
Many commercial cloud providers (Amazon, Rackspace, etc.) offer multiple regions and with OpenNebula is easy to create a distributed infrastructure thanks to Datacenter Federation option (oZone).
To manage the traffic between zones, many commercial cloud providers offer a dynamic DNS service integrated with a health check system to provide high availability, load balancing and geo resolution: the most well know are DynDNS and Amazon Route53.
In this speech I’ll make a brief introduction to the background: Anycast and all DNS techniques important to provide a valid Dynamic DNS based service, for example how to be dynamic but not slow and how to fight DDOS attacks.
After that, we “switch our view” to the customer and we talk about what the user needs and what it expect to find in a DNS service: in particular how to integrate a DNS service in an existing cloud infrastructure made with OpenNebula.