Require RHEL v8.4 or newer beginning with OpenShift v4.10

Author: jstuever

playbooks/scaleup.yml

@@ -1,5 +1,5 @@
 ---
-- name: Pre-scaleup checks
+- name: Pre-scaleup hostfile checks
   hosts: localhost
   connection: local
   gather_facts: no
@@ -8,6 +8,13 @@
       name: openshift_node
       tasks_from: scaleup_checks.yml
 
+- name: Pre-scaleup checks
+  hosts: new_workers
+  tasks:
+  - import_role:
+      name: openshift_node
+      tasks_from: version_checks.yml
+
 - name: install nodes
   hosts: new_workers
   roles:

playbooks/upgrade.yml

@@ -1,5 +1,5 @@
 ---
-- name: Pre-upgrade checks
+- name: Pre-upgrade hostfile checks
   hosts: localhost
   connection: local
   gather_facts: no
@@ -11,6 +11,13 @@
         workers host group to upgrade nodes
     when: groups.workers | default([]) | length == 0
 
+- name: Pre-upgrade checks
+  hosts: workers
+  tasks:
+  - import_role:
+      name: openshift_node
+      tasks_from: version_checks.yml
+
 - name: upgrade nodes
   hosts: workers
   serial: 1

roles/openshift_node/tasks/version_checks.yml

@@ -0,0 +1,25 @@
+---
+# This task file is run with import_role for localhost from scaleup.yml and upgrade.yml
+
+- name: Get cluster version
+  command: >
+    oc get clusterversion
+    --kubeconfig={{ openshift_node_kubeconfig_path }}
+    --output=jsonpath='{.items[0].status.desired.version}'
+  delegate_to: localhost
+  register: oc_get
+  until:
+  - oc_get.stdout != ''
+  changed_when: false
+
+- name: Set fact l_cluster_version
+  set_fact:
+    l_cluster_version: "{{ oc_get.stdout | regex_search('^\\d+\\.\\d+') }}"
+
+- name: Fail if not using RHEL8 beginning with version 4.10
+  fail:
+    msg: "As of v4.10, RHEL nodes must be at least version 8.4"
+  when:
+    - l_cluster_version is version('4.10', '>=')
+    - ansible_facts['distribution'] == "RedHat"
+    - ansible_facts['distribution_version'] is version('8.4', '<')