I was talking about different regions altogether, not just different AZs. My understanding is that it’s generally a bad idea in Kafka due to the latency, but I could be wrong.
EDIT:
Definitely sounds like there are some tight latency requirements[0]:
> A stretched 3-data center cluster architecture involves three data centers that are connected by a low latency (sub-100ms) and stable (very tight p99s) network, usually a “dark fiber” network that is owned or leased privately by the company.
100ms would theoretically be enough to span the contiguous United States, but the references to "very tight p99s" and "dark fiber" make me wonder if 100ms is actually acceptable, or just a theoretical maximum that can only be allowed under absolutely perfect conditions. Either way, suggesting the user should have access to dark fiber between their regions does not fill me with confidence about the robustness of this solution. I'm sure it would be fine for geographically close datacenters, as AZs are designed to be.
EDIT:
Definitely sounds like there are some tight latency requirements[0]:
> A stretched 3-data center cluster architecture involves three data centers that are connected by a low latency (sub-100ms) and stable (very tight p99s) network, usually a “dark fiber” network that is owned or leased privately by the company.
100ms would theoretically be enough to span the contiguous United States, but the references to "very tight p99s" and "dark fiber" make me wonder if 100ms is actually acceptable, or just a theoretical maximum that can only be allowed under absolutely perfect conditions. Either way, suggesting the user should have access to dark fiber between their regions does not fill me with confidence about the robustness of this solution. I'm sure it would be fine for geographically close datacenters, as AZs are designed to be.
[0]: https://docs.confluent.io/platform/current/multi-dc-deployme...