Cluster nodes
Cluster nodes are the nodes with which Kubernetes schedules application workloads. They are the workhorses of the cluster. A Kubernetes cluster can have a few, dozens, hundreds, or even thousands of cluster nodes. Kubernetes has been built from the ground up for high scalability. Don’t forget that Kubernetes was modeled on Google Borg, which has run tens of thousands of containers for years:
Figure 16.3 – Kubernetes worker node
A worker node – which is a cluster node, as are the master nodes – can run on a VM, bare metal, on-premises, or in the cloud. Originally, worker nodes could only be configured on Linux. But since version 1.10 of Kubernetes, worker nodes can also run on Windows Server 2010 or later. It is perfectly fine to have a mixed cluster with Linux and Windows worker nodes.
On each node, we have three services that need to run, as follows:
- Kubelet: This is the first and foremost service....