Re:Topology-Aware Service Routing on Kubernetes with Linkerd
by harpratap on Wednesday November 25, 2020 @07:27PM
(#25215794)
>A pod has no idea where its scheduled!
I would argue this is a good thing. All of the this automatic routing and failovers should be transparent to business logic developers. You shouldn't need to include K8s apis inside your main container.
Re:Topology-Aware Service Routing on Kubernetes with Linkerd
by The_rationalist on Wednesday November 25, 2020 @06:35PM
(#25215508)
keep workloads to their own zone depending on where they are. Hadoop achieve exactly that, I wonder if their solution could be used as an inspiration for solving this in kubernetes
The problem is that a pod has no easy way to know what topology it is in to make the choice to go to myservice-eu-west1a. The feature for getting topology labels through the downward api is not there! A pod has no idea where its scheduled!
The only way to find out is to ask the kubernetes api, but this requires rbac, a client, libraries etc.. unacceptable! Guess what linkerd does for you?
I am glad for the feature linkerd offers as it solves a problem and I can see the benefit of perhaps doing latency based routing as well on top of this.
It just ticks me off we need something complex to do something simple: keep workloads to their own zone depending on where they are.