Addressing multi-regional differences
ESG services are deployed to multiple active-active regions just like other autonomous services, but with one major difference. ESGs interact with external systems that may have very different architectures with different regional approaches. Addressing the differences is a multi-dimensional problem that can make your head spin as you consider the challenges from all angles:
- There is the perspective from your system and from the external system's.
- Whether the flow is egress or ingress.
- Are you using a push or pull technique?
- Is the external system in the cloud or on-premises?
- Is it active-active or active-passive?
- Does it perform regional routing or will you have to perform routing on the client side?
Following the happy path, a logical transaction starts with a user of your system being routed to the closest healthy region. From that point on, the chain of events and reactions happens in that region and...