kubeadm uses image tags (such as `v3.4.3-0`) to specify the version of
etcd. However, the upgrade code in kubeadm uses the etcd client API to
fetch the currently deployed version. The result contains only the etcd
version without the additional information (such as image revision) that
is normally found in the tag. As a result it would refuse an upgrade
where the etcd versions match and the only difference is the image
revision number (`v3.4.3-0` to `v3.4.3-1`).
To fix the above issue, the following changes are done:
- Replace the existing etcd version querying code, that uses the etcd
client library, with code that returns the etcd image tag from the
local static pod manifest file.
- If an etcd `imageTag` is specified in the ClusterConfiguration during
upgrade, use that tag instead. This is done regardless if the tag was
specified in the configuration stored in the cluster or with a new
configuration supplied by the `--config` command line parameter.
If no custom tag is specified, kubeadm will select one depending on
the desired Kubernetes version.
- `kubeadm upgrade plan` no longer prints upgrade information about
external etcd. It's the user's responsibility to manage it in that
case.
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>
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>
Used T.Run API for kubeadm tests in app/phases/selfhosting and
app/phases/update directories
This should improve testing output and make it more visible
which test is doing what.
Replaced hardcoded "v0.12.0" strings with MinimumControlPlaneVersion and
MinimumKubeletVersion global variables.
This should help with a regular release version bumps.
Bump MinimumControlPlaneVersion and MinimumKubeletVersion to v1.12 and update
any related tests.
Signed-off-by: Rostislav M. Georgiev <rostislavg@vmware.com>
Up until now UnifiedControlPlaneImage existed as a string value as part of the
ClusterConfiguration. This provided an override for the Kubernetes core
component images with a single custom image. It is mostly used to override the
control plane images with the hyperkube image. This saves both bandwith and
disk space on the control plane nodes.
Unfortunately, this specified an entire image string (complete with its prefix,
image name and tag). This disables upgrades of setups that use hyperkube.
Therefore, to enable upgrades on hyperkube setups and to make configuration
more convenient, the UnifiedControlPlaneImage option is replaced with a boolean
option, called UseHyperKubeImage. If set to true, this option replaces the
image name of any Kubernetes core components with hyperkube, thus allowing for
upgrades and respecting the image repository and version, specified in the
ClusterConfiguration.
Signed-off-by: Rostislav M. Georgiev <rostislavg@vmware.com>
In v1alpha3's, control plane component config options were nested directly into
the ClusterConfiguration structure. This is cluttering the config structure and
makes it hard to maintain. Therefore the control plane config options must be
separated into different substructures in order to graduate the format to beta.
This change does the following:
- Introduces a new structure called ControlPlaneComponent, that contains fields
common to all control plane component types. These are currently extra args
and extra volumes.
- Introduce a new structure called APIServer that contains
ControlPlaneComponent and APIServerCertSANs field (from ClusterConfiguration)
- Replace all API Server, Scheduler and Controller Manager options in
ClusterConfiguration with APIServer, ControllerManager and Scheduler fields
of APIServer and ControlPlaneComponent types.
Signed-off-by: Rostislav M. Georgiev <rostislavg@vmware.com>
When kubeadm upgrades a static pod cluster, the old manifests were previously
deleted. This patch alters this behaviour so they are now stored in a
timestamped temporary directory.
