Very interesting post by Raffaele Spazzoli published on OpenShift blog on topic of pod communication in multiple clusters. Istio, the upstream project for Red Hat OpenShift Mesh, has an interesting feature that allows you to extend the service mesh across multiple OpenShift clusters.
A pod in cluster A should be able to communicate with a pod in cluster B, assuming the pod in cluster A knows the IP address of the pod in cluster B.
The article focus on explaining the solution based on assumption that there was no direct connectivity between the nodes of the clusters involved in this design. If you don’t have that constraint, other potentially simpler designs become possible (for example ip over ip tunneling).
The article then explains in great deal:
- Tunnel design
- Encrypted tunnel design
- Routing packets
- Installation using Ansible playbook
You will also find explanatory schemas and links to further reading in the article.
Author thinks that the technology still needs to mature in this space and over time it will become much easier to implement these types of designs.
And do not forget that you can test OpenShift with free starter tier. Nicely done!
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