Last checked and updated on 10 Jun 2026
What Is New in Kubernetes 1.8
| Category | Key Highlights |
|---|---|
| Security | RBAC promoted to stable, Node authorizer, Client/Server TLS certificate rotation |
| Workloads | StatefulSet updates, PriorityClass preemption, Pod affinity/anti-affinity |
| Storage | External storage device health monitoring, FlexVolume resize, Local storage alpha |
| Networking | IPVS-based kube-proxy goes beta, CoreDNS alpha integration |
| API & Extensibility | CustomResourceDefinitions, API aggregation layer, Webhook admission control |
| Node & Cluster Lifecycle | Critical pods, CRI validation, kubeadm support for self-hosting |
How did Kubernetes 1.8 improve security controls?
Kubernetes 1.8 made significant strides in production-grade security. Role-Based Access Control (RBAC) moved to stable, providing a mature authorization system for controlling API access. The node authorizer was introduced to specifically handle authorization for kubelet requests, tightening node-level security.
Automatic TLS certificate rotation was implemented for both client credentials and serving certificates. This eliminates manual certificate management headaches while maintaining secure communications between all components. In practice, this means your cluster automatically handles credential renewal without service interruptions.
What workload management enhancements arrived in 1.8?
StatefulSets gained rolling update capabilities, finally allowing you to update stateful applications without taking them completely offline. The update strategies include rolling updates and partitioned updates, giving you fine-grained control over how your stateful applications evolve.
Pod priority and preemption entered beta, enabling critical pods to evict lower priority pods when resources become constrained. This matters because it ensures your cluster can prioritize system components and business-critical workloads during resource contention scenarios.
Pod affinity and anti-affinity moved to beta, providing more robust scheduling constraints. You could now express complex rules like "run these pods together on the same node" or "keep these pods separated across different availability zones."
What storage features were introduced in this release?
The release added external storage device health monitoring, allowing Kubernetes to detect and handle failed storage volumes. When a Persistent Volume becomes unhealthy, the system can automatically trigger appropriate recovery actions.
FlexVolume resize support entered alpha, enabling volume expansion for compatible storage plugins. Local storage also arrived as an alpha feature, letting you use directly-attached node storage for better performance on certain workloads.
How did networking evolve in Kubernetes 1.8?
IPVS-based kube-proxy graduated to beta, offering better performance and scalability for service routing compared to the traditional iptables approach. IPVS handles larger clusters more efficiently with lower latency for service IP routing.
CoreDNS integration appeared as an alpha feature, providing a DNS alternative to kube-dns built on a more flexible and extensible platform. This laid the groundwork for the plugin-based DNS architecture that would later become standard.
What API extensions and customizations became available?
CustomResourceDefinitions (CRD) reached stable status, replacing the older ThirdPartyResources with a more streamlined API for defining custom resources. This made it significantly easier to extend the Kubernetes API with your own resource types.
The API aggregation layer went stable, allowing you to extend the Kubernetes API with additional servers. Webhook admission control also reached beta, enabling custom validation and mutation of resources during admission phases through webhook callbacks.
FAQ
Is RBAC enabled by default in Kubernetes 1.8?
No, RBAC authorization mode is not enabled by default. You still need to explicitly enable it using the --authorization-mode=RBAC flag on the API server. However, since it's now stable, it's considered production-ready for those who choose to use it.
Can I perform rolling updates on StatefulSets in 1.8?
Yes, StatefulSet rolling updates are now supported through the updateStrategy field. You can configure either rolling updates or partitioned updates, allowing gradual updates of your stateful applications without complete downtime.
How does certificate rotation work in 1.8?
Kubernetes 1.8 introduces automatic rotation of both client TLS certificates and serving certificates. The kubelet automatically requests new certificates as old ones approach expiration, and the API server rotates its serving certificates without requiring restarts.
What's the benefit of IPVS over iptables for kube-proxy?
IPVS offers better performance and scalability for large clusters. It uses hash tables for efficient routing, resulting in lower latency for service IP resolution and better handling of thousands of services compared to iptables' linear chain processing.
Can I create custom resources without ThirdPartyResources in 1.8?
Yes, CustomResourceDefinitions (CRD) replaced ThirdPartyResources as the stable API for defining custom resources. CRDs are simpler to use and more efficient than the deprecated ThirdPartyResources, which were removed in this release.