c12s-kubespray/roles/docker/tasks/set_facts_dns.yml
woopstar e40368ae2b Add CoreDNS support with various fixes
Added CoreDNS to downloads

Updated with labels. Should now work without RBAC too

Fix DNS settings on hosts

Rename CoreDNS service from kube-dns to coredns

Add rotate based on http://edgeofsanity.net/rant/2017/12/20/systemd-resolved-is-broken.html

Updated docs with CoreDNS info

Added labels and fixed minor settings from official yaml file: https://github.com/kubernetes/kubernetes/blob/release-1.9/cluster/addons/dns/coredns.yaml.sed

Added a secondary deployment and secondary service ip. This is to mitigate dns timeouts and create high resitency for failures. See discussion at 'https://github.com/coreos/coreos-kubernetes/issues/641#issuecomment-281174806'

Set dns list correct. Thanks to @whereismyjetpack

Only download KubeDNS or CoreDNS if selected

Move dns cleanup to its own file and import tasks based on dns mode

Fix install of KubeDNS when dnsmask_kubedns mode is selected

Add new dns option coredns_dual for dual stack deployment. Added variable to configure replicas deployed. Updated docs for dual stack deployment. Removed rotate option in resolv.conf.

Run DNS manifests for CoreDNS and KubeDNS

Set skydns servers on dual stack deployment

Use only one template for CoreDNS dual deployment

Set correct cluster ip for the dns server
2018-03-16 21:51:37 +01:00

76 lines
2.5 KiB
YAML

---
- name: set dns server for docker
set_fact:
docker_dns_servers: |-
{%- if dns_mode in ['kubedns', 'coredns'] -%}
{{ [ skydns_server ] }}
{%- elif dns_mode == 'coredns_dual' -%}
{{ [ skydns_server ] + [ skydns_server_secondary ] }}
{%- elif dns_mode == 'dnsmasq_kubedns' -%}
{{ [ dnsmasq_dns_server ] }}
{%- elif dns_mode == 'manual' -%}
{{ [ manual_dns_server ] }}
{%- endif -%}
- name: set base docker dns facts
set_fact:
docker_dns_search_domains:
- 'default.svc.{{ dns_domain }}'
- 'svc.{{ dns_domain }}'
docker_dns_options:
- ndots:{{ ndots }}
- timeout:2
- attempts:2
- name: add upstream dns servers (only when dnsmasq is not used)
set_fact:
docker_dns_servers: "{{ docker_dns_servers + upstream_dns_servers|default([]) }}"
when: dns_mode in ['kubedns', 'coredns', 'coreos_dual']
- name: add global searchdomains
set_fact:
docker_dns_search_domains: "{{ docker_dns_search_domains + searchdomains|default([]) }}"
- name: check system nameservers
shell: grep "^nameserver" /etc/resolv.conf | sed 's/^nameserver\s*//'
changed_when: False
register: system_nameservers
check_mode: no
- name: check system search domains
shell: grep "^search" /etc/resolv.conf | sed 's/^search\s*//'
changed_when: False
register: system_search_domains
check_mode: no
- name: add system nameservers to docker options
set_fact:
docker_dns_servers: "{{ docker_dns_servers | union(system_nameservers.stdout_lines) | unique }}"
when: system_nameservers.stdout != ""
- name: add system search domains to docker options
set_fact:
docker_dns_search_domains: "{{ docker_dns_search_domains | union(system_search_domains.stdout.split()|default([])) | unique }}"
when: system_search_domains.stdout != ""
- name: check number of nameservers
fail:
msg: "Too many nameservers. You can relax this check by set docker_dns_servers_strict=no and we will only use the first 3."
when: docker_dns_servers|length > 3 and docker_dns_servers_strict|bool
- name: rtrim number of nameservers to 3
set_fact:
docker_dns_servers: "{{ docker_dns_servers[0:3] }}"
when: docker_dns_servers|length > 3 and not docker_dns_servers_strict|bool
- name: check number of search domains
fail:
msg: "Too many search domains"
when: docker_dns_search_domains|length > 6
- name: check length of search domains
fail:
msg: "Search domains exceeded limit of 256 characters"
when: docker_dns_search_domains|join(' ')|length > 256