Whenever kubeadm needs to fetch its configuration from the cluster, it gets
the component configuration of all supported components (currently only kubelet
and kube-proxy). However, kube-proxy is deemed an optional component and its
installation may be skipped (by skipping the addon/kube-proxy phase on init).
When kube-proxy's installation is skipped, its config map is not created and
all kubeadm operations, that fetch the config from the cluster, are bound to
fail with "not found" or "forbidden" (because of missing RBAC rules) errors.
To fix this issue, we have to ignore the 403 and 404 errors, returned on an
attempt to fetch kube-proxy's component config from the cluster.
The `GetFromKubeProxyConfigMap` function now supports returning nil for both
error and object to indicate just such a case.
Signed-off-by: Rostislav M. Georgiev <rostislavg@vmware.com>
MarshalClusterConfigurationToBytes has capabilities to output the component
configs, as separate YAML documents, besides the kubeadm ClusterConfiguration
kind. This is no longer necessary for the following reasons:
- All current use cases of this function require only the ClusterConfiguration.
- It will output component configs only if they are not the default ones. This
can produce undeterministic output and, thus, cause potential problems.
- There are only hacky ways to dump the ClusterConfiguration only (without the
component configs).
Hence, we simplify things by replacing the function with direct calls to the
underlaying MarshalToYamlForCodecs. Thus marshalling only ClusterConfiguration,
when needed.
Signed-off-by: Rostislav M. Georgiev <rostislavg@vmware.com>
During the control plane joins, sometimes the control plane returns an
expected error when trying to download the `kubeadm-config` ConfigMap.
This is a workaround for this issue until the root cause is completely
identified and fixed.
Ideally, this commit should be reverted in the near future.
Ever since v1alpha3, InitConfiguration is containing ClusterConfiguration
embedded in it. This was done to mimic the internal InitConfiguration, which in
turn is used throughout the kubeadm code base as if it is the old
MasterConfiguration of v1alpha2.
This, however, is confusing to users who vendor in kubeadm as the embedded
ClusterConfiguration inside InitConfiguration is not marshalled to YAML.
For this to happen, special care must be taken for the ClusterConfiguration
field to marshalled separately.
Thus, to make things smooth for users and to reduce third party exposure to
technical debt, this change removes ClusterConfiguration embedding from
InitConfiguration.
Signed-off-by: Rostislav M. Georgiev <rostislavg@vmware.com>
There are a couple of problems with regards to the `omitempty` in v1beta1:
- It is not applied to certain fields. This makes emitting YAML configuration
files in v1beta1 config format verbose by both kubeadm and third party Go
lang tools. Certain fields, that were never given an explicit value would
show up in the marshalled YAML document. This can cause confusion and even
misconfiguration.
- It can be used in inappropriate places. In this case it's used for fields,
that need to be always serialized. The only one such field at the moment is
`NodeRegistrationOptions.Taints`. If the `Taints` field is nil, then it's
defaulted to a slice containing a single control plane node taint. If it's
an empty slice, no taints are applied, thus, the cluster behaves differently.
With that in mind, a Go program, that uses v1beta1 with `omitempty` on the
`Taints` field has no way to specify an explicit empty slice of taints, as
this would get lost after marshalling to YAML.
To fix these issues the following is done in this change:
- A whole bunch of additional omitemptys are placed at many fields in v1beta2.
- `omitempty` is removed from `NodeRegistrationOptions.Taints`
- A test, that verifies the ability to specify empty slice value for `Taints`
is included.
Signed-off-by: Rostislav M. Georgiev <rostislavg@vmware.com>
This change introduces config fields to the v1beta2 format, that allow
certificate key to be specified in the config file. This certificate key is a
hex encoded AES key, that is used to encrypt certificates and keys, needed for
secondary control plane nodes to join. The same key is used for the decryption
during control plane join.
It is important to note, that this key is never uploaded to the cluster. It can
only be specified on either command line or the config file.
The new fields can be used like so:
---
apiVersion: kubeadm.k8s.io/v1beta2
kind: InitConfiguration
certificateKey: "yourSecretHere"
---
apiVersion: kubeadm.k8s.io/v1beta2
kind: JoinConfiguration
controlPlane:
certificateKey: "yourSecretHere"
---
Signed-off-by: Rostislav M. Georgiev <rostislavg@vmware.com>
These are based on recommendation from
[staticcheck](http://staticcheck.io/).
- Remove unused struct fields
- Remove unused function
- Remove unused variables
- Remove unused constants.
- Miscellaneous cleanups
In the case where newControlPlane is true we don't go through
getNodeRegistration() and initcfg.NodeRegistration.CRISocket is empty.
This forces DetectCRISocket() to be called later on, and if there is more than
one CRI installed on the system, it will error out, while asking for the user
to provide an override for the CRI socket. Even if the user provides an
override, the call to DetectCRISocket() can happen too early and thus ignore it
(while still erroring out).
However, if newControlPlane == true, initcfg.NodeRegistration is not used at
all and it's overwritten later on.
Thus it's necessary to supply some default value, that will avoid the call to
DetectCRISocket() and as initcfg.NodeRegistration is discarded, setting
whatever value here is harmless.
Signed-off-by: Rostislav M. Georgiev <rostislavg@vmware.com>
Add ResetClusterStatusForNode() that clears a certain
control-plane node's APIEndpoint from the ClusterStatus
key in the kubeadm ConfigMap on "kubeadm reset".
Currently kubeadm supports a couple of configuration versions - v1alpha3 and
v1beta1. The former is deprecated, but still supported.
To discourage users from using it and to speedup conversion to newer versions,
we disable the loading of deprecated configurations by all kubeadm
sub-commands, but "kubeadm config migrate".
v1alpha3 is still present and supported at source level, but cannot be used
directly with kubeadm and some of its internal APIs.
The added benefit to this is, that users won't need to lookup for an old
kubeadm binary after upgrade, just because they were stuck with a deprecated
config version for too long.
To achieve this, the following was done:
- ValidateSupportedVersion now has an allowDeprecated boolean parameter, that
controls if the function should return an error upon detecting deprecated
config version. Currently the only deprecated version is v1alpha3.
- ValidateSupportedVersion is made package private, because it's not used
outside of the package anyway.
- BytesToInitConfiguration and LoadJoinConfigurationFromFile are modified to
disallow loading of deprecated kubeadm config versions. An error message,
that points users to kubeadm config migrate is returned.
- MigrateOldConfig is still allowed to load deprecated kubeadm config versions.
- A bunch of tests were fixed to not expect success if v1alpha3 config is
supplied.
Signed-off-by: Rostislav M. Georgiev <rostislavg@vmware.com>
MigrateOldConfigFromFile is a function, whose purpose is to migrate one config
into another. It is working OK for now, but it has some issues:
- It is incredibly inefficient. It can reload and re-parse a single config file
for up to 3 times.
- Because of the reloads, it has to take a file containing the configuration
(not a byte slice as most of the rest config functions). However, it returns
the migrated config in a byte slice (rather asymmetric from the input
method).
- Due to the above points it's difficult to implement a proper interface for
deprecated kubeadm config versions.
To fix the issues of MigrateOldConfigFromFile, the following is done:
- Re-implement the function by removing the calls to file loading package
public APIs and replacing them with newly extracted package private APIs that
do the job with pre-provided input data in the form of
map[GroupVersionKind][]byte.
- Take a byte slice of the input configuration as an argument. This makes the
function input symmetric to its output. Also, it's now renamed to
MigrateOldConfig to represent the change from config file path as an input
to byte slice.
- As a bonus (actually forgotten from a previous change) BytesToInternalConfig
is renamed to the more descriptive BytesToInitConfiguration.
Signed-off-by: Rostislav M. Georgiev <rostislavg@vmware.com>
Add test files that exclude the field in question
under KubeletConfiguration -> evictionHard for non-Linux.
Add runtime abstraction for the test files in initconfiguration_tests.go
Currently ConfigFileAndDefaultsToInternalConfig and
FetchConfigFromFileOrCluster are used to default and load InitConfiguration
from file or cluster. These two APIs do a couple of completely separate things
depending on how they were invoked. In the case of
ConfigFileAndDefaultsToInternalConfig, an InitConfiguration could be either
defaulted with external override parameters, or loaded from file.
With FetchConfigFromFileOrCluster an InitConfiguration is either loaded from
file or from the config map in the cluster.
The two share both some functionality, but not enough code. They are also quite
difficult to use and sometimes even error prone.
To solve the issues, the following steps were taken:
- Introduce DefaultedInitConfiguration which returns defaulted version agnostic
InitConfiguration. The function takes InitConfiguration for overriding the
defaults.
- Introduce LoadInitConfigurationFromFile, which loads, converts, validates and
defaults an InitConfiguration from file.
- Introduce FetchInitConfigurationFromCluster that fetches InitConfiguration
from the config map.
- Reduce, when possible, the usage of ConfigFileAndDefaultsToInternalConfig by
replacing it with DefaultedInitConfiguration or LoadInitConfigurationFromFile
invocations.
- Replace all usages of FetchConfigFromFileOrCluster with calls to
LoadInitConfigurationFromFile or FetchInitConfigurationFromCluster.
- Delete FetchConfigFromFileOrCluster as it's no longer used.
- Rename ConfigFileAndDefaultsToInternalConfig to
LoadOrDefaultInitConfiguration in order to better describe what the function
is actually doing.
Signed-off-by: Rostislav M. Georgiev <rostislavg@vmware.com>
