diff --git a/slides/k8s/kubectlget.md b/slides/k8s/kubectlget.md index 451f9764..d1c034bb 100644 --- a/slides/k8s/kubectlget.md +++ b/slides/k8s/kubectlget.md @@ -442,3 +442,24 @@ class: extra-details - This file *does not* hold client keys or tokens - This is not sensitive information, but allows us to establish trust + +--- + +class: extra-details + +## What about `kube-node-lease`? + +- Starting with Kubernetes 1.14, there is a `kube-node-lease` namespace + + (or in Kubernetes 1.13 if the NodeLease feature gate is enabled) + +- That namespace contains one Lease object per node + +- *Node leases* are a new way to implement node heartbeats + + (i.e. node regularly pinging the control plane to say "I'm alive!") + +- For more details, see [KEP-0009] or the [node controller documentation] + +[KEP-0009]: https://github.com/kubernetes/enhancements/blob/master/keps/sig-node/0009-node-heartbeat.md +[node controller documentation]: https://kubernetes.io/docs/concepts/architecture/nodes/#node-controller \ No newline at end of file diff --git a/slides/k8s/namespaces.md b/slides/k8s/namespaces.md index 68261602..b1961073 100644 --- a/slides/k8s/namespaces.md +++ b/slides/k8s/namespaces.md @@ -26,13 +26,15 @@ ## Pre-existing namespaces -- If we deploy a cluster with `kubeadm`, we have three namespaces: +- If we deploy a cluster with `kubeadm`, we have three or four namespaces: - `default` (for our applications) - `kube-system` (for the control plane) - - `kube-public` (contains one secret used for cluster discovery) + - `kube-public` (contains one ConfigMap for cluster discovery) + + - `kube-node-lease` (in Kubernetes 1.14 and later; contains Lease objects) - If we deploy differently, we may have different namespaces