* Add an `enable_aggregation` variable to enable the kube-apiserver
aggregation layer for adding extension apiservers to clusters
* Aggregation is **disabled** by default. Typhoon recommends you not
enable aggregation. Consider whether less invasive ways to achieve your
goals are possible and whether those goals are well-founded
* Enabling aggregation and extension apiservers increases the attack
surface of a cluster and makes extensions a part of the control plane.
Admins must scrutinize and trust any extension apiserver used.
* Passing a v1.14 CNCF conformance test requires aggregation be enabled.
Having an option for aggregation keeps compliance, but retains the
stricter security posture on default clusters
* Refresh rules and dashboards from upstreams
* Add new Kubernetes "workload" dashboards
* View pods in a workload (deployment/daemonset/statefulset)
* View workloads in a namespace
* Define firewall rules on DigitialOcean to match rules used on AWS,
GCP, and Azure
* Output `controller_tag` and `worker_tag` to simplify custom firewall
rule creation
* 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
* 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
* 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)
* 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
* 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
* Add ServiceAccounts and ClusterRoleBindings for kube-apiserver
and kube-scheduler
* Remove the ClusterRoleBinding for the kube-system default ServiceAccount
* Rename the CA certificate CommonName for consistency with upstream
* T3 is the next generation general purpose burstable
instance type. Compared with t2.small, the t3.small is
cheaper, has 2 vCPU (instead of 1) and provides 5 Gbps
of pod-to-pod bandwidth (instead of 1 Gbps)
* Provide migration instructions for upgrading terraform-provider-ct
in-place for v1.12.2+ clusters
* Require switching from ~/.terraformrc to the Terraform third-party
plugins directory ~/.terraform.d/plugins/
* Require Container Linux 1688.5.3 or newer
* On GCP, kubectl port-forward connections to pods are closed
after a timeout (unlike AWS NLB's or Azure load balancers)
* Increase the GCP apiserver backend service timeout from 1 minute
to 5 minutes to be more similar to AWS/Azure LB behavior
* Example manifests aim to provide a read-only dashboard visible
to any users with network access (i.e. kubectl port-forward, LAN)
* Problem: Grafana always has an admin user, even with the user
management system disabled
* Disable the login form to prevent admin login
* Switch tutorials from using ~/.terraformrc to using the 3rd-party
plugin directory so 3rd-party plugins can be pinned
* Continue to show using terraform-provider-ct v0.2.2. Updating to
a newer version is only safe once all managed clusters are v1.12.2
or higher
* Calico Felix has been reporting anonymous usage data about the
version and cluster size, which violates Typhoon's privacy policy
where analytics should be opt-in only
* Add a variable enable_reporting (default: false) to allow opting
in to reporting usage data to Calico (or future components)
* Fix issue where Azure defaults to Deallocate eviction policy,
which required manually restarting deallocated workers
* Require terraform-provider-azurerm v1.19+ to support setting
the eviction_policy
* loop sends an initial query to detect infinite forwarding
loops in configured upstream DNS servers and fast exit with
an error (its a fatal misconfiguration on the network that
will otherwise cause resolvers to consume memory/CPU until
crashing, masking the problem)
* https://github.com/coredns/coredns/tree/master/plugin/loop
* loadbalance randomizes the ordering of A, AAAA, and MX records
in responses to provide round-robin load balancing (as usual,
clients may still cache responses though)
* https://github.com/coredns/coredns/tree/master/plugin/loadbalance
Dalton Hubble
yokhahn