Thought this wasn't required at first but I forgot there's no auto flush at the end of these tasks since the `kubernetes/master` role is not the end of the play.
* Fixes an issue where apiserver and friends (controller manager, scheduler) were prevented from restarting after manifests/secrets are changed. This occurred when a replaced kubelet doesn't reconcile new master manifests, which caused old master component versions to linger during deployment. In my case this was causing upgrades from k8s 1.6/1.7 -> k8s 1.8 to fail
* Improves transitions from kubelet container to host kubelet by preventing issues where kubelet container reappeared during the deployment
This allows `kube_apiserver_insecure_port` to be set to 0 (disabled). It's working, but so far I have had to:
1. Make the `uri` module "Wait for apiserver up" checks use `kube_apiserver_port` (HTTPS)
2. Add apiserver client cert/key to the "Wait for apiserver up" checks
3. Update apiserver liveness probe to use HTTPS ports
4. Set `kube_api_anonymous_auth` to true to allow liveness probe to hit apiserver's /healthz over HTTPS (livenessProbes can't use client cert/key unfortunately)
5. RBAC has to be enabled. Anonymous requests are in the `system:unauthenticated` group which is granted access to /healthz by one of RBAC's default ClusterRoleBindings. An equivalent ABAC rule could allow this as well.
Changes 1 and 2 should work for everyone, but 3, 4, and 5 require new coupling of currently independent configuration settings. So I also added a new settings check.
Options:
1. The problem goes away if you have both anonymous-auth and RBAC enabled. This is how kubeadm does it. This may be the best way to go since RBAC is already on by default but anonymous auth is not.
2. Include conditional templates to set a different liveness probe for possible combinations of `kube_apiserver_insecure_port = 0`, RBAC, and `kube_api_anonymous_auth` (won't be possible to cover every case without a guaranteed authorizer for the secure port)
3. Use basic auth headers for the liveness probe (I really don't like this, it adds a new dependency on basic auth which I'd also like to leave independently configurable, and it requires encoded passwords in the apiserver manifest)
Option 1 seems like the clear winner to me, but is there a reason we wouldn't want anonymous-auth on by default? The apiserver binary defaults anonymous-auth to true, but kubespray's default was false.
* Change deprecated vagrant ansible flag 'sudo' to 'become'
* Emphasize, that the name of the pip_pyton_modules is only considered in coreos
* Remove useless unused variable
* Fix warning when jinja2 template-delimiters used in when statement
There is no need for jinja2 template-delimiters like {{ }} or {% %}
any more. They can just be omitted as described in https://github.com/ansible/ansible/issues/22397
* Fix broken link in getting-started guide
* Change deprecated vagrant ansible flag 'sudo' to 'become'
* Workaround ansible bug where access var via dict doesn't get real value
When accessing a variable via it's name "{{ foo }}" its value is
retrieved. But when the variable value is retrieved via the vars-dict
"{{ vars['foo'] }}" this doesn't resolve the expression of the variable
any more due to a bug. So e.g. a expression foo="{{ 1 == 1 }}" isn't
longer resolved but just returned as string "1 == 1".
* Make file yamllint complient
When proxy vars are set, `uri` module tasks will attempt to route traffic through the proxy. This causes the "Wait for" tasks in the `etcd` and `kubernetes/master` roles to hang, as localhost connections struggle with a proxy.
As far as I know these roles only need local/cluster networking, so a proxy doesn't apply here anyway.
Some time ago I think the hardcoded `/var/lib/docker` was required, but kubelet running in a container has been aware of the Docker path since at least as far back as k8s 1.6.
Without this change, you see a large number of errors in the kubelet logs if you installed with a non-default `docker_daemon_graph`
