- During "upgrade apply" call a new function AddNewControlPlaneTaint()
that finds all nodes with the new "control-plane" node-role label
and adds the new "control-plane" taint to them.
- The function is called in "apply" and is separate from
the step to remove the old "master" label for better debugging
if errors occur.
- Rename the function in postupgrade.go to better reflect
what is being done.
- During "upgrade apply" find all nodes with the old label
and remove it by calling PatchNode.
- Update health check for CP nodes to not track "master"
labeled nodes. At this point all CP nodes should have
"control-plane" and we can use that selector only.
During "upgrade node" and "upgrade apply" read the
kubelet env file from /var/lib/kubelet/kubeadm-flags.env
patch the --container-runtime-endpoint flag value to
have the appropriate URL scheme prefix (e.g. unix:// on Linux)
and write the file back to disk.
This is a temporary workaround that should be kept only for 1 release
cycle - i.e. remove this in 1.25.
Panicing if not running in a test and if the component-base/version
variables are empty is not ideal. At some point sections
of kubeadm could be exposed as a library and if these sections
import the constants package, they would panic on the library
users unless they set the version information in component-base
with ldflags.
Instead:
- If the component-base version is empty, return a placeholder version
that should indicate to users that build kubeadm that something is not
right (e.g. they did not use 'make'). During library usage or unit
tests this version should not be relevant.
- Update unit tests to use hardcoded versions instead of the versions
from the constants package. Using the constants package for testing
is good but during unit tests these versions are already placeholders
since unit tests do not populate the actual component-base versions
(e.g. 1.23).
Tests under /app and /test would fail if the current/minimum k8s version
is dynamically populated from the version in the kubeadm binary.
Adapt the tests to support that.
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.
This is part of the "master" -> "control-plane" rename
that we missed. It's not critical for 1.21 as the
"control-plane" taint is still not added to CP nodes,
but it would be best to add the toleration preemptively
like the KEP planned.
Originally raised as an issue with invalid versions to plan, but it has
been determined with air gapped environments and development versions it
is not possible to fully address that issue.
But one thing that was identified was that we can do a better job in how
we output the upgrade plan information. Kubeadm outputs the requested
version as "Latest stable version", though that may not actually be the
case. For this instance, we want to change this to "Target version" to
be a little more accurate.
Then in the component upgrade table that is emitted, the last column of
AVAILABLE isn't quite right either. Also changing this to TARGET to
reflect that this is the version we are targetting to upgrade to,
regardless of its availability.
There could be some improvements in checking available versions,
particularly in air gapped environments, to make sure we actually have
access to the requested version. But this at least clarifies some of the
output a bit.
Signed-off-by: Sean McGinnis <sean.mcginnis@gmail.com>
Apply the label:
"node.kubernetes.io/exclude-from-external-load-balancers"
To control plane nodes to preserve backwards compatibility
with the legacy mode where "master" nodes were excluded from
LBs.
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.
A check that verifies that kubeadm does not "upgrade" to an older release was
overly optimized by skipping upgrade if the new version is the same as the old
one. This somewhat makes sense, but that way changes in any of the etcd fields
in the ClusterConfiguration won't be applied if the etcd version is not
changed.
Hence, this simple change ensures that the upgrade is done even when no version
change takes place.
Signed-off-by: Rostislav M. Georgiev <rostislavg@vmware.com>
