* 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)
* 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
* Fix a regression caused by lowering the Kubelet TLS client
certificate to system:nodes group (#100) since dropping
cluster-admin dropped the Kubelet's ability to delete nodes.
* On clouds where workers can scale down (manual terraform apply,
AWS spot termination, Azure low priority deletion), worker shutdown
runs the delete-node.service to remove a node to prevent NotReady
nodes from accumulating
* Allow Kubelets to delete cluster nodes via system:nodes group. Kubelets
acting with system:node and kubelet-delete ClusterRoles is still an
improvement over acting as cluster-admin
* DNS zones served by AWS Route53 may use AWS's special alias records
(other DNS providers would use a CNAME) to resolve the ingress NLB.
Alias records require the NLB DNS name's DNS zone id (not the cluster
`dns_zone_id`)
* System components that require certificates signed by the cluster
CA can submit a CSR to the apiserver, have an administrator inspect
and approve it, and be issued a certificate
* Configure kube-controller-manager to sign Approved CSR's using the
cluster CA private key
* Admins are responsible for approving or denying CSRs, otherwise,
no certificate is issued. Read the Kubernetes docs carefully and
verify the entity making the request and the authorization level
* https://kubernetes.io/docs/tasks/tls/managing-tls-in-a-cluster
Dalton Hubble