a) The current implementation use's a static kubelet which doesn't not conform to the Node authorization mode (i.e. system:nodes:<nodename>)
b) As present the kubeconfig is static and reused across all the masters and nodes
The PR firstly introduces the ability for users to use bootstrap tokens and secondly when enabled ensure the kubelets for the masters as have unique usernames. Note, this PR does not attempt to address the distribution of the bootstrap tokens themselves, that's for cluster admins. One solution for this would be a daemonset on the masters running on hostNetwork and reuse dns-controller to annotated the pods and give as the DNS
Notes:
- the master node do not use bootstrap tokens, instead given they have access to the ca anyhow, we generate certificates for each.
- when bootstrap token is not enabled the behaviour will stay the same; i.e. a kubelet configuration brought down from the store.
- when bootstrap tokens are enabled, the Nodes sit in a timeout loop waiting for the configuration to appear (by third party).
- given the nodeup docker and manifests builders are executed before the kubelet builder, the assumption here is a unit file kicks of a custom container to bootstrap the rest.
- the current firewalls on between the master and nodes are fairly open so no need to open ports between the two
- much of the work was ported from @justinsb PR [here](https://github.com/kubernetes/kops/pull/4134/)
- we add a very presumptuous server and client certificates for use with an authorizer (node-bootstrap-internal.dns_zone)
I do have an additional PR which performs the entire thing. The process being a node_authorizer which runs on the master nodes via a daemonset, the service implements a series of authorizers (i.e. alwaysallow, aws, gce etc). For aws, the process is similar to how vault authorizes nodes [here](https://www.vaultproject.io/docs/auth/aws.html). Nodeup no then calls out to the node_authorizer on bootstrap and provisions the kubelet.
Because the primary use-case is S3-style stores, we haven't really used
directories. If we have a use-case, we can always pass a boolean
parameter or create an alternative function.
File assets and the SHA files are uploaded to the new location. Files
when are users uses s3 are upload public read only. The copyfile task
uses only the existing SHA value.
This PR include major refactoring of the use of URLs. Strings are no
longer categnated, but converted into a URL struct and path.Join is
utlilized.
A new values.go file is included so that we can start refactoring more
code out of the "fi" package.
A
This lets us configure cross-project permissions while ourselves needing
minimal permissions, but also gives us a nice hook for future lockdown
of object-level permissions.
This ensures that the cluster can read the kops state store files, even
if the GCS bucket is in a different project.
We automatically set up an IAM access policy that grants access.
Justin Santa Barbara