kubeadm's current implementation of component config support is "kind" centric.
This has its downsides. Namely:
- Kind names and numbers can change between config versions.
Newer kinds can be ignored. Therefore, detection of a version change is
considerably harder.
- A component config can have only one kind that is managed by kubeadm.
Thus a more appropriate way to identify component configs is required.
Probably the best solution identified so far is a config group.
A group name is unlikely to change between versions, while the kind names and
structure can.
Tracking component configs by group name allows us to:
- Spot more easily config version changes and manage alternate versions.
- Support more than one kind in a config group/version.
- Abstract component configs by hiding their exact structure.
Hence, this change rips off the old kind based support for component configs
and replaces it with a group name based one. This also has the following
extra benefits:
- More tests were added.
- kubeadm now errors out if an unsupported version of a known component group
is used.
Signed-off-by: Rostislav M. Georgiev <rostislavg@vmware.com>
This change removes dependencies on the internal types of the kubelet and
kube-proxy component configs. Along with that defaulting and validation is
removed as well. kubeadm will display a warning, that it did not verify the
component config upon load.
Signed-off-by: Rostislav M. Georgiev <rostislavg@vmware.com>
For historical reasons InitConfiguration is used almost everywhere in kubeadm
as a carrier of various configuration components such as ClusterConfiguration,
local API server endpoint, node registration settings, etc.
Since v1alpha2, InitConfiguration is meant to be used solely as a way to supply
the kubeadm init configuration from a config file. Its usage outside of this
context is caused by technical dept, it's clunky and requires hacks to fetch a
working InitConfiguration from the cluster (as it's not stored in the config
map in its entirety).
This change is a small step towards removing all unnecessary usages of
InitConfiguration. It reduces its usage by replacing it in some places with
some of the following:
- ClusterConfiguration only.
- APIEndpoint (as local API server endpoint).
- NodeRegistrationOptions only.
- Some combinations of the above types, or if single fields from them are used,
only those field.
Signed-off-by: Rostislav M. Georgiev <rostislavg@vmware.com>
Bump MinimumControlPlaneVersion and MinimumKubeletVersion to v1.12 and update
any related tests.
Signed-off-by: Rostislav M. Georgiev <rostislavg@vmware.com>
