* Add HA docs for API server.
* Add auto-evaluated internal endpoints and clarify the loadbalancer_apiserver
vars and usecases.
* Use facts for kube_apiserver to not repeat code and enable LB endpoints use.
* Use /healthz check for the wait-for apiserver.
* Use the single endpoint for kubelet instead of the list of apiservers
* Specify kube_apiserver_count to for HA layout
Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>
kubelet via docker
kube-apiserver as a static pod
Fixed etcd service start to be more tolerant of slow start.
Workaround for kube_version to stay in download role, but not
download an files by creating a new "nothing" download entry.
* Enforce a etcd-proxy role to a k8s-cluster group members. This
provides an HA layout for all of the k8s cluster internal clients.
* Proxies to be run on each node in the group as a separate etcd
instances with a readwrite proxy mode and listen the given endpoint,
which is either the access_ip:2379 or the localhost:2379.
* A notion for the 'kube_etcd_multiaccess' is: ignore endpoints and
loadbalancers and use the etcd members IPs as a comma-separated
list. Otherwise, clients shall use the local endpoint provided by a
etcd-proxy instances on each etcd node. A Netwroking plugins always
use that access mode.
* Fix apiserver's etcd servers args to use the etcd_access_endpoint.
* Fix networking plugins flannel/calico to use the etcd_endpoint.
* Fix name env var for non masters to be set as well.
* Fix etcd_client_url was not used anywhere and other etcd_* facts
evaluation was duplicated in a few places.
* Define proxy modes only in the env file, if not a master. Del
an automatic proxy mode decisions for etcd nodes in init/unit scripts.
* Use Wants= instead of Requires= as "This is the recommended way to
hook start-up of one unit to the start-up of another unit"
* Make apiserver/calico Wants= etcd-proxy to keep it always up
Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>
Co-authored-by: Matthew Mosesohn <mmosesohn@mirantis.com>
Kubernetes API server has an option:
```
--advertise-address=<nil>: The IP address on which to advertise the apiserver to members of the cluster. This address must be reachable by the rest of the cluster. If blank, the --bind-address will be used. If --bind-address is unspecified, the host's default interface will be used.
```
kargo does not set --bind-address, thus it binds to eth0, in vagrant and similar
environments this causes issues because nodes cannot talk to eachother over eth0.
This sets `--advertise-address` to `ip` if its set, otherwise the default behavior
of is persisted by using `ansible_default_ipv4.address`.
Each node can have 3 IPs.
1. ansible_default_ip4 - whatever ansible things is the first IPv4 address
usually with the default gw.
2. ip - An address to use on the local node to bind listeners and do local
communication. For example, Vagrant boxes have a first address that is the
NAT bridge and is common for all nodes. The second address/interface should
be used.
3. access_ip - An address to use for node-to-node access. This is assumed to
be used by other nodes to access the node and may not be actually assigned
on the node. For example, AWS public ip that is not assigned to node.
This updates the places addresses are used to use either ip or access_ip and walk
up the list to find an address.
