Thank you for the correction regarding Azure! I knew they had a CNI plugin, but did't realize it has the limitations you describe (I've only used GCP and AWS).
> I've not had a problem with CoreDNS? Ours seems to cope fine at about
> 500 requests / min. The bigger problem is stuff in the cluster being
> really irresponsible about how many DNS queries they make…
My expectation for DNS is that name lookups should function at thousands of requests per second. Serving that kind of QPS implies caching, and thus some sort of update notification -- for example watching the EndpointSlices resource for changes, and pushing them directly into the DNS server's state.
(As you might notice from my article + employment history, my expectations around cluster sizes differs from the community norm.)
(As you might notice from my article + employment history, my expectations around cluster sizes differs from the community norm.)