OpenShift Node Operations

External

• https://docs.openshift.com/container-platform/3.5/admin_guide/manage_nodes.html

Internal

• OpenShift Operations

Overview

A node is a Linux container host. More details about nodes are available here:

OpenShift Concepts - Nodes

Getting Information about a Node

oc get nodes
oc get node <node-name>
oc describe node/<node-name>

Get Labels Applied to a Node

Get Labels Applied to a Node

Update Labels on a Node

TODO: https://docs.openshift.com/container-platform/3.5/admin_guide/manage_nodes.html#updating-labels-on-nodes

Other Procedures

• Make a node schedulable/unschedulable

Adding a New Node

https://docs.openshift.com/container-platform/3.5/install_config/adding_hosts_to_existing_cluster.html#adding-nodes-advanced

New nodes can be added with the scaleup.yml playbook. The playbook generates and distributes new certificates for the new hosts, then runs the configuration playbook on the new hosts only. However, before running the playbook, the host must be prepared in the same way the other nodes were. If the nodes were created based on a template, the same template should be used to stand up the new node. For more details, see:

OpenShift 3.5 Installation Procedure - Node Configuration

Use the same Ansible inventory file that was used to install the rest of the cluster.

On the Ansible host, update to the latest version of 'atomic-openshift-utils'

yum update atomic-openshift-utils

In the Ansible inventory file, add "new_<host_type> to the [OSEv3:children] section:

[OSEv3:children]
masters
etcd
nodes
new_nodes
lb
nfs

Create a [new_<host_type>] section following the patterns already in place for the similar types of nodes:

[new_nodes]

node3.local openshift_node_labels="{'logging':'true', 'cluster':'noper430', 'env':'lab'}"

Removing a Node

TODO: https://docs.openshift.com/container-platform/3.5/admin_guide/manage_nodes.html#deleting-nodes