Initially this was removed, but it turns out that services that
perform reverse lookups (such as MariaDB) will encounter severe
performance degredation with this disabled.

Change method to set use_hyperkube_cni var bool

Allow subdomains of dns_domain and fix kubelet restarts

Restored gather facts on all hosts

The precedent method returb a string "True\n" or "False\n", it seems to be an Ansible bug.
New method return a boolean

Fix containers download condition

use variable dns_domain instead of cluster_name for kubedns

* Add a var for ndots (default 5) and put it hosts' /etc/resolv.conf.
* Poke kube dns container image to v1.7
* In order to apply changes to kubelet, notify it to
be restarted on changes made to /etc/resolv.conf. Ignore errors as the kubelet
may yet to be present up to the moment of the notification being processed.
* Remove unnecessary kubelet restart for master role as the node role ensures
it is up and running. Notify master static pods waiters for apiserver,
scheduler, controller-manager instead.

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

Save/push/load containers if only download.enabled and download.container

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

Correct nslookup command

Add more DNS docs

Copy hyperkube CNI plugins when using weave

Add Docker 1.12.1 version

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

Change nslookup command to check the right cluster_name

Adjust DNS picture

Reflect changes made to DNS setup

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

Fix docs and dns servers placement order

- Update docs and a drawing to clarify DNS setup.
- Change order of nameservers placement to match
  changes in https://github.com/kubespray/kargo/pull/501



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

Make dnsmasq daemon set optional

Change additional dnsmasq opts:
- Adjust caching size and TTL
- Disable resolve conf to not create loops
- Change dnsPolicy to default (similarly to kubedns's dnsmasq). The
  ClusterFirst should not be used to not create loops
- Disable negative NXDOMAIN replies to be cached
- Make its very installation as optional step (enabled by default).
  If you don't want more than 3 DNS servers, including 1 for K8s, disable
  it.
- Add docs and a drawing to clarify DNS setup.
- Fix stdout logs for dnsmasq/kubedns app configs
- Add missed notifies to resolvconf -u handler
- Fix idempotency of resolvconf head file changes

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

Improve management of nameservers in resolv.conf

Changing nameservers now will clean up previous entries

Changed ImagePullPolicy from Always to IfNotPresent to avoid download…

Rename large-deploymets.md to large-deployments.md

Filename was a typo

Fix reverse DNS lookups of service IPs.

always bind etcd_proxy to localhost

Add socat do required pkgs

switch /etc/hosts to use blockinfile

This fixes "DNS should provide DNS for services [Conformance]"
e2e test in k8s.

Fix use_hyperkube_cni logic

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

Distribute container images across nodes