Kubeadm no longer supports kube-dns and CoreDNS is the only
supported DNS server. Remove ClusterConfiguration.DNS.Type
from v1beta3 that is used to set the DNS server type.
During upgrade the coredns migration library seems to require
that the input version doesn't have the "v" prefix".
Fixes a bug where the user cannot run commands such as
"kubeadm upgrade plan" if they have `v1.8.0` installed.
Assuming this is caused by the fact that previously the image didn't
have a "v" prefix.
- Mark the "node-role.kubernetes.io/master" key for labels
and taints as deprecated.
- During "kubeadm init/join" apply the label
"node-role.kubernetes.io/control-plane" to new control-plane nodes,
next to the existing "node-role.kubernetes.io/master" label.
- During "kubeadm upgrade apply", find all Nodes with the "master"
label and also apply the "control-plane" label to them
(if they don't have it).
- During upgrade health-checks collect Nodes labeled both "master"
and "control-plane".
- Rename the constants.ControlPlane{Taint|Toleraton} to
constants.OldControlPlane{Taint|Toleraton} to manage the transition.
- Mark constants.OldControlPlane{{Taint|Toleraton} as deprecated.
- Use constants.OldControlPlane{{Taint|Toleraton} instead of
constants.ControlPlane{Taint|Toleraton} everywhere.
- Introduce constants.ControlPlane{Taint|Toleraton}.
- Add constants.ControlPlaneToleraton to the kube-dns / CoreDNS
Deployments to make them anticipate the introduction
of the "node-role.kubernetes.io/control-plane:NoSchedule"
taint (constants.ControlPlaneTaint) on kubeadm control-plane Nodes.
The isCoreDNSVersionSupported() check assumes that
there is a running kubelet, that manages the CoreDNS containers.
If the containers are being created it is not possible to fetch
their image digest. To workaround that, a poll can be used in
isCoreDNSVersionSupported() and wait for the CoreDNS Pods
are expected to be running. Depending on timing and CNI
yet to be installed this can cause problems related to
addon idempotency of "kubeadm init", because if the CoreDNS
Pods are waiting for another step they will never get running.
Remove the function isCoreDNSVersionSupported() and assume that
the version is always supported. Rely on the Corefile migration
library to error out if it must.
A narrow assumption of what is contained in the `imageID` fields for the
CoreDNS pods causes a panic upon upgrade.
Fix this by using a proper regex to match a trailing SHA256 image digest
in `imageID` or return an error if it cannot find it.
Signed-off-by: Rostislav M. Georgiev <rostislavg@vmware.com>
of service subnets.
Update DNS, Cert, dry-run logic to support list of Service CIDRs.
Added unit tests for GetKubernetesServiceCIDR and updated
GetDNSIP() unit test to inclue dual-sack cases.
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>
As kube-dns transitioned to fat manifests, it's no longer required to use arch
suffixed images. This change makes use of fat manifests for kube-dns and
removes the last few calls to the GetGenericArchImage function, thus removing
GetGenericArchImage too.
Signed-off-by: Rostislav M. Georgiev <rostislavg@vmware.com>
Some code in kubeadm was designed with the intent, that in the future CoreDNS
and kube-dns versions will match to specific K8s versions. This code is not
functional, since it does not perform any version matching. As of this moment,
no version matching is planned and a lot of boilerplate code is left useless.
The solution is simple - remove the unneeded parts to simplify the flow.
Signed-off-by: Rostislav M. Georgiev <rostislavg@vmware.com>
