Description of problem:
Between  z-streams of 3.11 openshift_hostname started being ignored. The playbook doens't fail immediately.

I'm setting high severity and high priority because the bug is identified and has huge potential impact


Version-Release number of the following components:
Customer reproduced this on 3.10.73-1 but 3.10.87-1 should also be affected
openshift_hostname used to work on openshift-ansible-3.10.47-1

How reproducible:
Always

Steps to Reproduce:
1. Specify a hostname using openshift_hostname instead of openshift_kubelet_name_override
2. Verify openshift_facts

Actual results:
openshift_hostname is ignored, the playbook keeps running with a wrong value.

This has a huge impact because it can break certificates and make several components connect to unexpected endpoints.

Expected results:
openshift_hostname is either honored with a deprecation warning or causes the playbook to fail if it's different openshift_kubelet_name_override

Additional info:


$ git diff 95bc2d2  playbooks/init/validate_hostnames.yml
diff --git a/playbooks/init/validate_hostnames.yml b/playbooks/init/validate_hostnames.yml
index b37e6fec4..ca280684b 100644
--- a/playbooks/init/validate_hostnames.yml
+++ b/playbooks/init/validate_hostnames.yml
@@ -10,19 +10,20 @@
     changed_when: false
     failed_when: false
 
-  - name: Validate openshift_hostname when defined
+  - name: Validate openshift_kubelet_name_override when defined
     fail:
       msg: >
         The hostname {{ openshift.common.hostname }} for {{ ansible_nodename }}
         doesn't resolve to an IP address owned by this host. Please set
-        openshift_hostname variable to a hostname that when resolved on the host
+        openshift_kubelet_name_override variable to a hostname that when resolved on the host
         in question resolves to an IP address matching an interface on this host.
         This will ensure proper functionality of OpenShift networking features.
-        Inventory setting: openshift_hostname={{ openshift_hostname | default ('undefined') }}
+        Inventory setting: openshift_kubelet_name_override={{ openshift_kubelet_name_override | default ('undefined') }}
         This check can be overridden by setting openshift_hostname_check=false in
         the inventory.
         See https://docs.openshift.org/latest/install_config/install/advanced_install.html#configuring-host-variables
     when:
+    - openshift_kubelet_name_override is defined
     - lookupip.stdout != '127.0.0.1'
     - lookupip.stdout not in ansible_all_ipv4_addresses
     - openshift_hostname_check | default(true) | bool

$ git blame playbooks/init/validate_hostnames.yml | grep kubelet_name_override
5ce5800906 playbooks/init/validate_hostnames.yml                     (Michael Gugino      2018-10-05 10:22:35 -0400 13)   - name: Validate openshift_kubelet_name_override when defined
5ce5800906 playbooks/init/validate_hostnames.yml                     (Michael Gugino      2018-10-05 10:22:35 -0400 18)         openshift_kubelet_name_override variable to a hostname that when resolved on the host
5ce5800906 playbooks/init/validate_hostnames.yml                     (Michael Gugino      2018-10-05 10:22:35 -0400 21)         Inventory setting: openshift_kubelet_name_override={{ openshift_kubelet_name_override | default ('undefined') }}
5ce5800906 playbooks/init/validate_hostnames.yml                     (Michael Gugino      2018-10-05 10:22:35 -0400 26)     - openshift_kubelet_name_override is defined

$ git show 5ce5800906 --summary
commit 5ce5800906255a2a6bf940a17908be59d9861de7
Author: Michael Gugino <mgugino@redhat.com>
Date:   Fri Oct 5 10:22:35 2018 -0400

    Fail on openshift_hostname defined; add openshift_kubelet_name_override
    
    Adding openshift_kubelet_name_override as a stand-in for
    various places we will need to account for possible hostname
    overrides.
    
    (cherry picked from commit 1faee0942dec05b6f652669ad6cfced986a0cbc9)
    (cherry picked from commit 8d3509838c7ecc2bafafa7f7815b9964bf08cdda)