When the etcd cluster grows we need to explicitly wait for it to be
available. This ensures that we are not implicitly doing this in
following steps when they try to access the apiserver.
Despite we were checking for the kubelet kubeconfig file to be present, the
kubelet first writes this file and then the certificates the kubeconfig file
refers to. This represents a race condition in kubeadm in which when we confirm
that the kubelet's kubeconfig file is present we continue creating a clientset
out of it. However, the clientset creation will ensure that the certificates the
kubeconfig file refers to exist on the filesystem.
To fix this problem, not only wait for the kubelet's kubeconfig file to be
present, but also ensure that we can create a clientset ouf of it on our polling
process, while we wait for the kubelet to have performed the TLS bootstrap.
'kubeadm init' silently ignores --node-name and --cri-socket
command line options if --config option is specified.
Implemented setting 'name' and 'criSocket' options from the command
line even if --config command line option is used.
kubeadm config migrate uses AnyConfigFileAndDefaultsToInternal, which can
unmarshal config from file only if InitConfiguration or JoinConfiguration are
present. Even with that in mind, it can only return a singlie config object,
with InitConfiguration taking precendence over JoinConfiguration. Thus, the
following cases were not handled properly, while they were perfectly valid for
kubeadm init/join:
- ClusterConfiguration only file caused kubeadm config migrate to exit with
error.
- Init + Join configurations in the same file caused Init + Cluster
configuration to be produced (ignoring JoinConfiguration). The same is valid
when the combo is Init + Cluster + Join configurations.
- Cluster + Join configuration ignores ClusterConfiguration and only
JoinConfiguration gets migrated.
To fix this, the following is done:
- Introduce MigrateOldConfigFromFile which migrates old config from a file,
while ensuring that all kubeadm originated input config kinds are taken care
of. Add comprehensive unit tests for this.
- Replace the use of AnyConfigFileAndDefaultsToInternal in
kubeadm config migrate with MigrateOldConfigFromFile.
- Remove the no longer used and error prone AnyConfigFileAndDefaultsToInternal.
Signed-off-by: Rostislav M. Georgiev <rostislavg@vmware.com>