Handle all old dns domains:
- for nodelocaldns: in the same server block as the current dns_domain
- for coredns: uffix rewrite of each of the old dns domains to the
  current one

Signed-off-by: Maxime Leroy <19607336+maxime1907@users.noreply.github.com>

Fix a broken link to KEP 0030 in the dns-stack docs,
which has been merged into KEP 1024.

* Ability to define options for DNS upstream servers

* Doc and sample inventory vars

Signed-off-by: eminaktas <eminaktas34@gmail.com>

Signed-off-by: eminaktas <eminaktas34@gmail.com>

Using the coredns_cluster_zone_cache_block variable

refs #8247

* nodelocaldns: allow a secondary pod for nodelocaldns for local-HA

* CI: add job to test nodelocaldns secondary

* created variable to enable/disable reverse dns lookups in coredns

* fixed linting-error in dns-stack.md

* Moved docker_dns_options to defaults so it can be overridden

* Fixed yaml indentation and markdown

* Moved docker_dns_search_domains to defaults

Allows to add custom zone resolving servers.

Allows to configure additionnal zone for domains not resolved by `upstream_dns_servers`.

Fix http link to https link for security

Signed-off-by: Nguyen Hai Truong <truongnh@vn.fujitsu.com>

* Minor cleanups

* Add comment in docs that nodelocaldns cache is enabled by default

Both kubedns and dnsmasq modes are long not maintained.
We should run dns_late steps at the end because sshd
makes DNS lookups during Ansible run and has 2s timeouts
for each failed lookup trying to connect to coredns before
it is ready.

since bad886ca, dns_mode is set to coredns by default instead of kubedns

* Add support for running a nodelocal dns cache

After encountering dns issues in a cluster I was recently working on I
noticed Kubernetes 1.13 introduced support for running a nodelocal dns
cache.

I believe this can usefull for more people.

https://github.com/kubernetes/kubernetes/commit/73b548db06c5e293533344c5b6171e955eac9ff1
https://github.com/kubernetes/enhancements/blob/master/keps/sig-network/0030-nodelocal-dns-cache.md

* Add requested changes

* Add additional requested changes + documentation

* Add requested changes after review

* Replace incorrect variable

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

Also update reset.yml to do more dns/network related cleanup.

Also fix kube log level 4 to log dnsmasq queries.

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>

Also fix kube log level 4 to log dnsmasq queries.

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>
Co-authored-by: Matthew Mosesohn <mmosesohn@mirantis.com>

Do not repeat options and nameservers in the dhclient hooks.
Do not prepend nameservers for dhclient but supersede and fail back
to the upstream_dns_resolvers then default_resolver. Fixes order of
nameservers placement, which is cluster DNS ip goes always first.

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>

* For Debian/RedHat OS families (with NetworkManager/dhclient/resolvconf
  optionally enabled) prepend /etc/resolv.conf with required nameservers,
  options, and supersede domain and search domains via the dhclient/resolvconf
  hooks.

* Drop (z)nodnsupdate dhclient hook and re-implement it to complement the
  resolvconf -u command, which is distro/cloud provider specific.
  Update docs as well.

* Enable network restart to apply and persist changes and simplify handlers
  to rely on network restart only. This fixes DNS resolve for hostnet K8s
  pods for Red Hat OS family. Skip network restart for canal/calico plugins,
  unless https://github.com/projectcalico/felix/issues/1185

 fixed.

* Replace linefiles line plus with_items to block mode as it's faster.

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>
Co-authored-by: Matthew Mosesohn <mmosesohn@mirantis.com>