* Allow multi-controller clusters on Google Cloud
* GCP regional network load balancers have a long open
bug in which requests originating from a backend instance
are routed to the instance itself, regardless of whether
the health check passes or not. As a result, only the 0th
controller node registers. We've recommended just using
single master GCP clusters for a while
* https://issuetracker.google.com/issues/67366622
* Workaround issue by switching to a GCP TCP Proxy load
balancer. TCP proxy lb routes traffic to a backend service
(global) of instance group backends. In our case, spread
controllers across 3 zones (all regions have 3+ zones) and
organize them in 3 zonal unmanaged instance groups that
serve as backends. Allows multi-controller cluster creation
* GCP network load balancers only allowed legacy HTTP health
checks so kubelet 10255 was checked as an approximation of
controller health. Replace with TCP apiserver health checks
to detect unhealth or unresponsive apiservers.
* Drawbacks: GCP provision time increases, tailed logs now
timeout (similar tradeoff in AWS), controllers only span 3
zones instead of the exact number in the region
* Workaround in Typhoon has been known and posted for 5 months,
but there still appears to be no better alternative. Its
probably time to support multi-master and accept the downsides
* Set defaults for internal worker module's count,
machine_type, and os_image
* Allow "pools" of homogeneous workers to be created
using the google-cloud/kubernetes/workers module
* Upcoming releases may begin to use features that require
the `terraform-provider-ct` plugin v0.2.1
* New users should use `terraform-provider-ct` v0.2.1. Existing
users can safely drop-in replace their v0.2.0 plugin with v0.2.1
as well (location referenced in ~/.terraformrc).
* See https://github.com/poseidon/typhoon/pull/145
* Add flannel service account and limited RBAC cluster role
* Change DaemonSets to tolerate NoSchedule and NoExecute taints
* Remove deprecated apiserver --etcd-quorum-read flag
* Update Calico from v3.0.1 to v3.0.2
* Add Calico GlobalNetworkSet CRD
* https://github.com/poseidon/terraform-render-bootkube/pull/44
* Add explicit "providers" section to modules for Terraform v0.11.x
* Retain support for Terraform v0.10.4+
* Add migration guide from Terraform v0.10.x to v0.11.x for those managing
existing clusters (action required!)
* Be sure docs and examples list Container Linux versions that
have been patched for Meltdown just in case someone copy-pastes
or sees them as recent versions
* Allow kube-dns to respond to DNS queries with a custom
suffix, instead of the default 'cluster.local'
* Useful when multiple clusters exist on the same local
network and wish to query services on one another
* Container Linux stable and beta now provide Docker 17.09 (instead
of 1.12). Recommend images which provide 17.09.
* Older clusters (with CLUO addon) auto-update node's Container Linux version
and will begin using Docker 17.09.
* Change controllers from a managed group to individual instances
* Create discrete DNS records to each controller's private IP for etcd
* Change etcd to run on-host, across controllers (etcd-member.service)
* Reduce time to bootstrap a cluster
* Deprecate self-hosted-etcd on the Google Cloud platform
* Controller preemption is not safe or covered in documentation. Delete
the option, the variable is a holdover from old experiments
* Note, worker_preemeptible is still a great feature that's supported
* Change Google Cloud module to require the `region` variable
* Workers are created in random zones within the given region
* Tolerate Google Cloud zone failures or capacity issues
* If workers are preempted (if enabled), replacement instances can
be drawn from any zone in the region, which should avoid scheduling
issues that were possible before if a single zone aggressively
preempts instances (presumably due to Google Cloud capacity)
* Kubernetes v1.8.2 fixes a memory leak in the v1.8.1 apiserver
* Switch to using the `gcr.io/google_containers/hyperkube` for the
on-host kubelet and shutdown drains
* Update terraform-render-bootkube manifests generation
* Update flannel from v0.8.0 to v0.9.0
* Add `hairpinMode` to flannel CNI config
* Add `--no-negcache` to kube-dns dnsmasq
