Use helm install or support in future

The number of pods on a given node is determined by the  --max-pods=k
directive. When the address space is exhausted, no more pods can be
scheduled even if from the --max-pods-perspective, the node still has
capacity.

The special case that a pod is scheduled and uses the node IP in the
host network namespace is too "soft" to derive a guarantee.

Comparing kubelet_max_pods with kube_network_node_prefix when given
allows to assert that pod limits match the CIDR address space.

* Move front-proxy-client certs back to kube mount

We want the same CA for all k8s certs

* Refactor vault to use a third party module

The module adds idempotency and reduces some of the repetitive
logic in the vault role

Requires ansible-modules-hashivault on ansible node and hvac
on the vault hosts themselves

Add upgrade test scenario
Remove bootstrap-os tags from tasks

* fix upgrade issues

* improve unseal logic

* specify ca and fix etcd check

* Fix initialization check

bump machine size

* sysctl file should be in defaults so that it can be overriden

* Change sysctl_file_path to be consistent with roles/kubernetes/preinstall/defaults/main.yml

This reverts commit 51f4e658.

Add support for installing package dependencies and refreshing metadata
on SUSE distributions

Co-authored-by: Nirmoy Das <ndas@suse.de>

* Add pre-upgrade task for moving credentials file

This reverts commit 7ef9f4df.

* add python interpreter workaround for localhost

This file should only be updated during kubelet upgrade so that
master components are not accidentally restarted first during
preinstall stage.

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

* Added cilium support

* Fix typo in debian test config

* Remove empty lines

* Changed cilium version from <latest> to <v1.0.0-rc3>

* Add missing changes for cilium

* Add cilium to CI pipeline

* Fix wrong file name

* Check kernel version for cilium

* fixed ci error

* fixed cilium-ds.j2 template

* added waiting for cilium pods to run

* Fixed missing EOF

* Fixed trailing spaces

* Fixed trailing spaces

* Fixed trailing spaces

* Fixed too many blank lines

* Updated tolerations,annotations in cilium DS template

* Set cilium_version to iptables-1.9 to see if bug is fixed in CI

* Update cilium image tag to v1.0.0-rc4

* Update Cilium test case CI vars filenames

* Add optional prometheus flag, adjust initial readiness delay

* Update README.md with cilium info

Ansible automatically installs the python-apt package when using
the 'apt' Ansible module, if python-apt is not present. This patch
removes the (unneeded) explicit installation in the Kubespray
'preinstall' role.

1.Disalbe install epel-release rpm on Centos/Redhat
2.Use yum install epel-release

Cloud resolvers are mandatory for hosts on GCE and OpenStack
clouds. The 8.8.8.8 alternative resolver was dropped because
there is already a default nameserver. The new var name
reflects the purpose better.

Also restart apiserver when modifying dns settings.

import_tasks will consume far less memory, so it should be
used whenever it is compatible.

* Adding changes to handle updation of yum cache in rhel.

* Removed the redundant spaces