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>
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>
Replaced hardcoded "v0.12.0" strings with MinimumControlPlaneVersion and
MinimumKubeletVersion global variables.
This should help with a regular release version bumps.
