* Run at least two replicas of CoreDNS to better support
rolling updates (previously, kube-dns had a pod nanny)
* On multi-master clusters, set the CoreDNS replica count
to match the number of masters (e.g. a 3-master cluster
previously used replicas:1, now replicas:3)
* Add AntiAffinity preferred rule to favor distributing
CoreDNS pods across controller nodes nodes
* Continue to ensure scheduler and controller-manager run
at least two replicas to support performing kubectl edits
on single-master clusters (no change)
* For multi-master clusters, set scheduler / controller-manager
replica count to the number of masters (e.g. a 3-master cluster
previously used replicas:2, now replicas:3)
* Require a terraform-provider-digitalocean plugin version of
1.0 or higher within the same major version (e.g. allow 1.1 but
not 2.0)
* Change requirement from ~> 0.1.2 (which allowed up to but not
including 1.0 release)
* Add new bird and felix readiness checks
* Read MTU from ConfigMap veth_mtu
* Add RBAC read for serviceaccounts
* Remove invalid description from CRDs
* Release v1.11.1 erroneously left Fedora Atomic clusters using
the v1.11.0 Kubelet. The rest of the control plane ran v1.11.1
as expected
* Update Kubelet from v1.11.0 to v1.11.1 so Fedora Atomic matches
Container Linux
* Container Linux modules were not affected
* Adjust firewall rules, security groups, cloud load balancers,
and generated kubeconfig's
* Facilitates some future simplifications and cost reductions
* Bare-Metal users who exposed kube-apiserver on a WAN via their
router or load balancer will need to adjust its configuration.
This is uncommon, most apiserver are on LAN and/or behind VPN
so no routing infrastructure is configured with the port number
* Raise minimum Terraform version to v0.11.0
* Terraform v0.11.x has been supported since Typhoon v1.9.2
and Terraform v0.10.x was last released in Nov 2017. I'd like
to stop worrying about v0.10.x and remove migration docs as
a later followup
* Migration docs docs/topics/maintenance.md#terraform-v011x
* (containerized) kube-proxy warns that it is unable to
load the ip_vs kernel module despite having the correct
mounts. Atomic uses an xz compressed module and modprobe
in the container was not compiled with compression support
* Workaround issue for now by always loading ip_vs on-host
* https://github.com/kubernetes/kubernetes/issues/60
* Use the upstream bootkube image packaged with the
required metadata to be usable as a system container
under systemd
* Run bootkube with runc so no host level components
use Docker any more. Docker is still the runtime
* Remove bootkube script and old systemd unit
* Change kubelet system image to use --cgroups-per-qos=true
(default) instead of false
* Change kubelet system image to use --enforce-node-allocatable=pods
instead of an empty string
* Fix kubelet port-forward on Google Cloud / Fedora Atomic
* Mount the host's /etc/hosts in kubelet system containers
* Problem: kubelet runc system containers on Atomic were not
mounting the host's /etc/hosts, like rkt-fly does on Container
Linux. `kubectl port-forward` calls socat with localhost. DNS
servers on AWS, DO, and in many bare-metal environments resolve
localhost to the caller as a convenience. Google Cloud notably
does not nor is it required to do so and this surfaced the
missing /etc/hosts in runc kubelet namespaces.