From 2ba4e9bda5d645ddb4c34065284d80b2c2ba6042 Mon Sep 17 00:00:00 2001
From: Matthew Mosesohn <matthew.mosesohn@gmail.com>
Date: Thu, 1 Nov 2018 18:08:50 +0300
Subject: [PATCH] Skip most of kubernetes/preinstall role during late DNS
 config (#3627)

When using resolvconf_mode host_resolvconf, there is an early DNS
config stage where Kubernetes cluster DNS is not injected for host
DNS intially. Later, the cluster DNS is enabled, but we do not
need to run every task from the kubernetes/preinstall role.
---
 cluster.yml                                   |  2 +-
 roles/kubernetes/preinstall/defaults/main.yml |  1 +
 roles/kubernetes/preinstall/tasks/main.yml    | 21 ++++++++++++++++++-
 3 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/cluster.yml b/cluster.yml
index 45dcefb31..143657906 100644
--- a/cluster.yml
+++ b/cluster.yml
@@ -126,7 +126,7 @@
   roles:
     - { role: kubespray-defaults}
     - { role: dnsmasq, when: "dns_mode == 'dnsmasq_kubedns'", tags: dnsmasq }
-    - { role: kubernetes/preinstall, when: "dns_mode != 'none' and resolvconf_mode == 'host_resolvconf'", tags: resolvconf }
+    - { role: kubernetes/preinstall, when: "dns_mode != 'none' and resolvconf_mode == 'host_resolvconf'", tags: resolvconf, dns_late: true }
   environment: "{{proxy_env}}"
 
 - hosts: kube-master
diff --git a/roles/kubernetes/preinstall/defaults/main.yml b/roles/kubernetes/preinstall/defaults/main.yml
index 30ad182b3..0cd9b0f16 100644
--- a/roles/kubernetes/preinstall/defaults/main.yml
+++ b/roles/kubernetes/preinstall/defaults/main.yml
@@ -5,6 +5,7 @@ run_gitinfos: false
 ignore_assert_errors: false
 
 epel_enabled: false
+dns_late: false
 
 common_required_pkgs:
   - python-httplib2
diff --git a/roles/kubernetes/preinstall/tasks/main.yml b/roles/kubernetes/preinstall/tasks/main.yml
index 2505101e8..0d9d6b3bd 100644
--- a/roles/kubernetes/preinstall/tasks/main.yml
+++ b/roles/kubernetes/preinstall/tasks/main.yml
@@ -1,24 +1,34 @@
 ---
 # Disable swap
 - import_tasks: 0010-swapoff.yml
-  when: disable_swap
+  when:
+    - not dns_late
+    - disable_swap
 
 - import_tasks: 0020-verify-settings.yml
+  when:
+    - not dns_late
   tags:
     - asserts
 
 # This is run before bin_dir is pinned because these tasks are run on localhost
 - import_tasks: 0030-pre_upgrade.yml
   run_once: true
+  when:
+    - not dns_late
   tags:
     - upgrade
 
 - import_tasks: 0040-set_facts.yml
+  when:
+    - not dns_late
   tags:
     - resolvconf
     - facts
 
 - import_tasks: 0050-create_directories.yml
+  when:
+    - not dns_late
 
 - import_tasks: 0060-resolvconf.yml
   when:
@@ -29,14 +39,20 @@
     - resolvconf
 
 - import_tasks: 0070-system-packages.yml
+  when:
+    - not dns_late
   tags:
     - bootstrap-os
 
 - import_tasks: 0080-system-configurations.yml
+  when:
+    - not dns_late
   tags:
     - bootstrap-os
 
 - import_tasks: 0090-etchosts.yml
+  when:
+    - not dns_late
   tags:
     - bootstrap-os
     - etchosts
@@ -67,11 +83,14 @@
   stat:
     path: /var/lib/waagent/
   register: azure_check
+  when:
+    - not dns_late
   tags:
     - bootstrap-os
 
 - import_tasks: 0120-growpart-azure-centos-7.yml
   when:
+    - not dns_late
     - azure_check.stat.exists
     - ansible_distribution in ["CentOS","RedHat"]
   tags: