c12s-kubespray/roles/kubernetes/preinstall/tasks/set_resolv_facts.yml
Bogdan Dobrelya 1782d19e1f Fallback to default resolver if no nameservers
Current design expects users to define at least one
nameserver in the nameservers var to backup host OS DNS config
when the K8s cluster DNS service IP is not available and hosts
still have to resolve external or intranet FQDNs.

Fix undefined nameservers to fallback to the default_resolver.

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>
2016-12-16 14:51:34 +01:00

83 lines
2.8 KiB
YAML

---
- name: check resolvconf
shell: which resolvconf
register: resolvconf
ignore_errors: yes
changed_when: false
- set_fact:
resolvconf: >-
{%- if resolvconf.rc == 0 -%}true{%- else -%}false{%- endif -%}
- set_fact:
private_domains: |-
{% for d in [ 'default.svc.' + dns_domain, 'svc.' + dns_domain ] + searchdomains|default([]) -%}
{{dns_domain}}.{{d}}./{{d}}.{{d}}./com.{{d}}./
{%- endfor %}
default_resolver: >-
{%- if cloud_provider is defined and cloud_provider == 'gce' -%}169.254.169.254{%- else -%}8.8.8.8{%- endif -%}
- name: check kubelet
stat:
path: "{{ bin_dir }}/kubelet"
register: kubelet
changed_when: false
- name: check if early DNS configuration stage
set_fact:
dns_early: >-
{%- if kubelet.stat.exists -%}false{%- else -%}true{%- endif -%}
- name: target resolv.conf files
set_fact:
resolvconffile: /etc/resolv.conf
base: >-
{%- if resolvconf|bool -%}/etc/resolvconf/resolv.conf.d/base{%- endif -%}
head: >-
{%- if resolvconf|bool -%}/etc/resolvconf/resolv.conf.d/head{%- endif -%}
when: ansible_os_family != "CoreOS"
- name: target temporary resolvconf cloud init file (CoreOS)
set_fact: resolvconffile=/tmp/resolveconf_cloud_init_conf
when: ansible_os_family == "CoreOS"
- name: target dhclient conf/hook files for Red Hat family
set_fact:
dhclientconffile: /etc/dhcp/dhclient.conf
dhclienthookfile: /etc/dhcp/dhclient.d/zdnsupdate.sh
when: ansible_os_family == "RedHat"
- name: target dhclient conf/hook files for Debian family
set_fact:
dhclientconffile: /etc/dhcp/dhclient.conf
dhclienthookfile: /etc/dhcp/dhclient-exit-hooks.d/zdnsupdate
when: ansible_os_family == "Debian"
- name: generate search domains to resolvconf
set_fact:
searchentries:
search {{ ([ 'default.svc.' + dns_domain, 'svc.' + dns_domain ] + searchdomains|default([])) | join(' ') }}
domainentry:
domain {{ dns_domain }}
supersede_search:
supersede domain-search "{{ ([ 'default.svc.' + dns_domain, 'svc.' + dns_domain ] + searchdomains|default([])) | join('", "') }}";
supersede_domain:
supersede domain-name "{{ dns_domain }}";
- name: pick dnsmasq cluster IP or default resolver
set_fact:
dnsmasq_server: |-
{%- if skip_dnsmasq|bool and not dns_early|bool -%}
{{ [ skydns_server ] + upstream_dns_servers|default([]) }}
{%- elif dns_early|bool -%}
{{ upstream_dns_servers|default([]) }}
{%- else -%}
{{ [ dns_server ] }}
{%- endif -%}
- name: generate nameservers to resolvconf
set_fact:
nameserverentries:
nameserver {{( dnsmasq_server + nameservers|default([default_resolver])) | join(',nameserver ')}}
supersede_nameserver:
supersede domain-name-servers {{( dnsmasq_server + nameservers|default([default_resolver])) | join(', ') }};