Hey everyone! I'm in the midst of reevaluating our Kubernetes (K8s) architecture for an on-prem deployment and really need some insights. We currently have a network divided into zones for different functions, such as utility services (like card access and HVAC), business functions, a primary DMZ, and various other zones. I'm trying to shift towards a flatter, more efficient model, but right now, we're stuck with a setup that involves multiple Rancher clusters: one for development/QA and another for production for every zone. This means we're managing around 12-15 clusters! The K8s team keeps requesting more nodes for performance boosts, even though resource usage is quite low on the current nodes.
I'm beginning to think we might've misconfigured things. What if instead of multiple clusters across the zones, we consolidated to a single production cluster in the DMZ and controlled access via firewalls and ingress? Plus, should we run QA and dev workloads in the main cluster with restrictions instead of separating them into different clusters? Also, I believe scaling up might be more effective than scaling out, considering bare-metal options might be better than virtualized setups. We're currently looking at approaching 80 Rancher VMs over these clusters, and I'd appreciate your thoughts on how to streamline this chaotic setup!
3 Answers
I think the different zones you're mentioning are generating some confusion. It sounds like you might be treating zones as physical locations rather than logical separations. If the primary concern is security, using separate clusters is a solid approach. However, I find it curious that the K8s team is requesting more nodes for performance—more nodes don't necessarily boost performance, it can even lead to the opposite if not managed well. It might benefit you to look at your workloads and reassess whether those scaling requests are truly necessary.
Your instincts are right on target! Reducing the number of clusters while implementing proper multi-tenancy could really simplify your architecture. You might want to set up just one or two clusters for non-production workloads alongside a management cluster for Rancher. This way, you can align tenant isolation with your business structure and implement resource quotas and limits in namespaces. It's all about scaling up within your hypervisor before you think about scaling out to keep things efficient.
I understand your frustration with the numerous clusters. We also faced similar challenges and decided to consolidate by using a shared control plane for our clusters. This way, we managed to reduce complexity and improve security without sacrificing the benefits of multi-tenancy. If your zones aren't strictly necessary, using namespaces for different environments could be a game-changer! Also, be sure to discuss horizontal scaling options, as increasing pod counts might be more effective than just adding nodes.
Agreed! It sounds more like a fundamental misunderstanding of how K8s should be utilized. Instead of treating it like just another app, the infrastructure should be viewed as a full-fledged environment with its own networking controls. I'd also suggest leveraging tools to help manage complexity in configurations—something like a service mesh could greatly assist with traffic management.