* This change affects users who use worker pools on AWS, GCP, or
Azure with a Container Linux derivative
* Rename worker pool modules' `count` variable to `worker_count`,
because `count` will be a reserved variable name in Terraform v0.12
* Add ability to load balance TCP applications (e.g. NodePort)
* Output the network load balancer ARN as `nlb_id`
* Accept a `worker_target_groups` (ARN) list to which worker
instances should be added
* AWS NLBs and target groups don't support UDP
* Kubelets can use a lower-privilege TLS client certificate with
Org system:nodes and a binding to the system:node ClusterRole
* Admin kubeconfig's continue to belong to Org system:masters to
provide cluster-admin (available in assets/auth/kubeconfig or as
a Terraform output kubeconfig-admin)
* Remove bare-metal output variable kubeconfig
* Replace os_channel variable with os_image to align naming
across clouds. Users who set this option to stable, beta, or
alpha should now set os_image to coreos-stable, coreos-beta,
or coreos-alpha.
* Default os_image to coreos-stable. This continues to use
the most recent image from the stable channel as always.
* Allow Container Linux derivative Flatcar Linux by setting
os_image to `flatcar-stable`, `flatcar-beta`, `flatcar-alpha`
* Add `worker_price` to allow worker spot instances. Defaults
to empty string for the worker autoscaling group to use regular
on-demand instances.
* Add `spot_price` to internal `workers` module for spot worker
pools
* Note: Unlike GCP `preemptible` workers, spot instances require
you to pick a bid price.
* Introduce the ability to support Container Linux Config
"snippets" for controllers and workers on cloud platforms.
This allows end-users to customize hosts by providing Container
Linux configs that are additively merged into the base configs
defined by Typhoon. Config snippets are validated, merged, and
show any errors during `terraform plan`
* Example uses include adding systemd units, network configs,
mounts, files, raid arrays, or other disk provisioning features
provided by Container Linux Configs (using Ignition low-level)
* Requires terraform-provider-ct v0.2.1 plugin
* Allow groups of workers to be defined and joined to
a cluster (i.e. worker pools)
* Move worker resources into a Terraform submodule
* Output variables needed for passing to worker pools
* Add usage docs for AWS worker pools (advanced)
* Template terraform-render-bootkube's multi-line kubeconfig
output using the right indentation
* Add `kubeconfig` variable to google-cloud controllers and
workers Terraform submodules
* Remove `kubeconfig_*` variables from google-cloud controllers
and workers Terraform submodules
* 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
Dalton Hubble
Jordan Pittier
Barak Michener