How does submariner do coordination between the controllers in the two clusters?

[kapilagrawal95]

Hi,

I have a fundamental question about submariner. Does submariner's broker synchronizes the etcd of each cluster as well? For example, if I have a deployment which I would like to ensure are spread uniformly across both the clusters? How will the coordination between the controllers be in such a situation?

Thanks in advance!

[tpantelis]

The broker is just a namespace to which participating clusters read and write CRs to share them between the clusters.

[kapilagrawal95]

So does it mean that a global view (etcd) is not available to the kubernetes cluster? And therefore, the use-case I mentioned of spreading replicas across clusters is not supported by submariner currently?

[tpantelis]

I assume you're asking if submariner shares the entire K8s DB across clusters. No - it only shares CRs that are necessary for submariner to function properly. Anything else is out-of-scope for the purpose of submariner.

[sridhargaddam]

Adding to what @tpantelis mentioned, you can take a look at the Architecture page to understand how Submariner uses the Broker - https://submariner.io/getting-started/architecture/broker/