* Background: A managed instance group of workers is used in backend
services for global load balancing (HTTP/HTTPS Ingress) and output
for custom global load balancing use cases
* Add worker instances to a target pool load balancing TCP/UDP
applications (NodePort or proxied). Output as `worker_target_pool`
* Health check for workers with a healthy Ingress controller. Forward
rules (regional) to target pools don't support different external and
internal ports so choosing nodes with Ingress allows proxying as a
workaround
* A target pool is a logical grouping only. It doesn't add costs to
clusters or worker pools
* Allow traffic from Grafana to Prometheus in monitoring
* Allow traffic from Prometheus to Prometheus in monitoring
* NetworkPolicy denies non-whitelisted traffic. Define policy
to allow other access
* Set resource requests and limits for Grafana and CLUO
* Set resource requests for Prometheus, but allow usage
to grow since needs vary widely
* Leave nginx without resource requests/limits for now,
its typically well behaved
* Add calico-ipam CRDs and RBAC permissions
* Switch IPAM from host-local to calico-ipam
* `calico-ipam` subnets `ippools` (defaults to pod CIDR) into
`ipamblocks` (defaults to /26, but set to /24 in Typhoon)
* `host-local` subnets the pod CIDR based on the node PodCIDR
field (set via kube-controller-manager as /24's)
* Create a custom default IPv4 IPPool to ensure the block size
is kept at /24 to allow 110 pods per node (Kubernetes default)
* Retaining host-local was slightly preferred, but Calico v3.6
is migrating all usage to calico-ipam. The codepath that skipped
calico-ipam for KDD was removed
* https://docs.projectcalico.org/v3.6/release-notes/
* Heapster addon powers `kubectl top`
* In early Kubernetes, people legitimately used and expected
`kubectl top` to work, so the optional addon was provided
* Today the standards are different. Many better monitoring
tools exist, that are also less coupled to Kubernetes "kubectl
top" reliance on a non-core extensions means its not in-scope
for minimal Kubernetes clusters. No more exceptionalism
* Finally, Heapster isn't that useful anymore. Its manifests
have no need for Typhoon-specific modification
* Look to prior releases if you still wish to apply heapster
* Restore the original special-casing of DigitalOcean Kubelets
* Fix node metadata InternalIP being set to the IP of the default
gateway on DigitalOcean nodes (regressed in v1.12.3)
* Reverts the "pretty" node names on DigitalOcean (worker-2 vs IP)
* Closes#424 (full details)
* Require an iPXE-enabled network boot environment with support for
TLS downloads. PXE clients must chainload to iPXE firmware compiled
with `DOWNLOAD_PROTO_HTTPS` enabled ([crypto](https://ipxe.org/crypto))
* iPXE's pre-compiled firmware binaries do _not_ enable HTTPS. Admins
should build iPXE from source with support enabled
* Affects the Container Linux and Flatcar Linux install profiles that
pull from public downloads. No effect when cached_install=true
or using Fedora Atomic, as those download from Matchbox
* Add `download_protocol` variable. Recognizing boot firmware TLS
support is difficult in some environments, set the protocol to "http"
for the old behavior (discouraged)
* Allow terraform-provider-aws >= v1.13, but < 3.0. No change
to the minimum version, but allow using v2.x.y releases
* Verify compatability with terraform-provider-aws v2.1.0
* Resolve in-addr.arpa and ip6.arpa DNS PTR requests for Kubernetes
service IPs and pod IPs
* Previously, CoreDNS was configured to resolve in-addr.arpa PTR
records for service IPs (but not pod IPs)
* Minimum versions of Terraform provider plugins are enforced in
each module already. Its better to provide examples with newer
versions. Some folks don't update them
* Previously, tutorials showed the minimum viable version of each
terraform provider that might be used
* Show creation of a PXE-enabled network boot environment when
using dnsmasq as the DHCP server
* Recommend TFTP be served from /config/tftpboot since /config
is preserved between firmware upgrades
* Recommend compiling undionly.kpxe from source to enable
TLS features
* Add a note that equal-cost multi-path service IP routing
(e.g. for ingress) requires EdgeOS v2.0. Previously, it was known
that TLS handshakes couldn't be completed with packet balacing.
I've verified this is no longer the case when using the v2.0
EdgeOS firmware, ECMP works as expected.
* Support terraform-provider-google v1.19.0, v1.19.1, v1.20.0
and v2.0+ (and allow for future 2.x.y releases)
* Require terraform-provider-google v1.19.0 or newer. v1.19.0
introduced `network_interface` fields `network_ip` and `nat_ip`
to deprecate `address` and `assigned_nat_ip`. Those deprecated
fields are removed in terraform-provider-google v2.0
* https://github.com/terraform-providers/terraform-provider-google/releases/tag/v2.0.0
* Assign pod priorityClassNames to critical cluster and node
components (higher is higher priority) to inform node out-of-resource
eviction order and scheduler preemption and scheduling order
* Priority Admission Controller has been enabled since Typhoon
v1.11.1
* Intel Haswell or better is available in every zone around the world
* Neither Kubernetes nor Typhoon have a particular minimum processor
family. However, a few Google Cloud zones still default to Sandy/Ivy
bridge (scheduled to shift April 2019). Price is only based on machine
type so it is beneficial to opt for the next processor family
* Intel Haswell is a suitable minimum since it still allows plenty of
liberty in choosing any region or machine type
* Likely a slight increase to preemption probability in a few zones,
but any lower probability on Sandy/Ivy bridge is due to lower
desirability as they're phased out
* https://cloud.google.com/compute/docs/regions-zones/
* Collate upstream rules, alerts, and dashboards and tune for use
in Typhoon
* Previously, a well-chosen (but older) set of rules, alerts, and
dashboards were maintained to reflect metric name changes
* Prometheus queries from some upstreams use joins of node-exporter
and kube-state-metrics metrics by (namespace,pod). Add the Kubernetes
pod name to service endpoint metrics
* Rename the kubernetes_namespace field to namespace
* Honor labels since kube-state-metrics already include a `pod` field
that should not be overridden
Dalton Hubble