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>
Automatic merge from submit-queue (batch tested with PRs 63717, 64646, 64792, 64784, 64800). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
kubeadm: Upload CRISocket information in kubeadm init/join
**What this PR does / why we need it**:
As a side-effect, `kubeadm join` will become blocking on the kubelet doing the TLS bootstrap. This partially also fixes problems when users run `kubeadm join` and it returns successfully without anything happening as the kubelet is actually unhealthy. If that happens now `kubeadm join` will exit with a non-zero code.
What this PR does is it uploads the CRISocket information to the Node API object as a workaround until we have something like https://github.com/kubernetes/kubernetes/issues/64460 in place that will solve this problem for real. This way we won't lose the CRISocket information which we would otherwise do.
This can be used for `kubeadm upgrade` or `kubeadm reset` in future releases.
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes #
**Special notes for your reviewer**:
Depends on https://github.com/kubernetes/kubernetes/pull/64624
**Release note**:
```release-note
[action required] TODO
```
@kubernetes/sig-cluster-lifecycle-pr-reviews
Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
kubeadm: When etcd is listening on all interfaces, set the etcd probe to use loopback
**What this PR does / why we need it**:
When constructing the etcd liveness probe, if the user passes an IPv4 or IPv6 address,
we set the `etcdctl` liveness probe to use the respective IPv4 or IPv6 loopback address for `--endpoints`.
The etcd probe is now always formatted with the https:// protocol and square brackets around the IP (required for IPv6 / compatible with IPv4).
`::1` is now also included in the etcd serving cert SAN by default.
/kind bug
/area kubeadm
/area etcd
/priority important-soon
/sig cluster-lifecycle
/assign @fabriziopandini
**Which issue(s) this PR fixes**
Fixes https://github.com/kubernetes/kubeadm/issues/882
**Special notes for your reviewer**:
```bash
root@vagrant:~# /vagrant/bin/882_kubeadm init --config /dev/stdin << EOF |& tail -n5
etcd:
extraArgs:
listen-client-urls: https://[::]:2379
EOF
I0603 19:52:15.666594 24743 tlsbootstrap.go:50] [bootstraptoken] configured RBAC rules to allow Node Bootstrap tokens to post CSRs in order for nodes to get long term certificate credentials
I0603 19:52:15.671424 24743 tlsbootstrap.go:72] [bootstraptoken] configured RBAC rules to allow the csrapprover controller automatically approve CSRs from a Node Bootstrap Token
I0603 19:52:15.674607 24743 tlsbootstrap.go:95] [bootstraptoken] configured RBAC rules to allow certificate rotation for all node client certificates in the cluster
I0603 19:52:15.677551 24743 clusterinfo.go:43] [bootstraptoken] creating the "cluster-info" ConfigMap in the "kube-public" namespace
[addons] Applied essential addon: CoreDNS
[addons] Applied essential addon: kube-proxy
root@vagrant:~# cat /etc/kubernetes/manifests/etcd.yaml |grep -C4 listen
spec:
containers:
- command:
- etcd
- --listen-client-urls=https://[::]:2379
- --advertise-client-urls=https://127.0.0.1:2379
- --cert-file=/etc/kubernetes/pki/etcd/server.crt
- --client-cert-auth=true
- --data-dir=/var/lib/etcd
root@vagrant:~# cat /etc/kubernetes/manifests/etcd.yaml |grep -C4 etcdctl
exec:
command:
- /bin/sh
- -ec
- ETCDCTL_API=3 etcdctl --endpoints=https://[::1]:2379 --cacert=/etc/kubernetes/pki/etcd/ca.crt
--cert=/etc/kubernetes/pki/etcd/healthcheck-client.crt --key=/etc/kubernetes/pki/etcd/healthcheck-client.key
get foo
failureThreshold: 8
initialDelaySeconds: 15
```
**Release note**:
```release-note
kubeadm now configures the etcd liveness probe correctly when etcd is listening on all interfaces
```
Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
kubeadm: Let the `--node-name` flag flow down to `--hostname-override` for the kubelet
**What this PR does / why we need it**:
Kubeadm-initialised kubelet uses provided hostname if present
If --node-name is passed in to `kubeadm init`, `--hostname-override` will be
passed to kubelet. This prevents timeout errors for `kubeadm init`.
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes kubernetes/kubeadm#846
**Special notes for your reviewer**:
Depends on #64624 to work fully, but can safely merged before hand.
**Release note**:
```release-note
[action required] The `--node-name` flag for kubeadm now dictates the Node API object name the
kubelet uses for registration, in all cases but where you might use an in-tree cloud provider.
If you're not using an in-tree cloud provider, `--node-name` will set the Node API object name.
If you're using an in-tree cloud provider, you MUST make `--node-name` match the name the
in-tree cloud provider decides to use.
```
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CoreDNS to use gcr.io repo
**What this PR does / why we need it**:
Switch CoreDNS to use the gcr.io in kubeadm
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes #
**Special notes for your reviewer**:
**Release note**:
```release-note
CoreDNS deployment configuration now uses k8s.gcr.io imageRepository
```
Automatic merge from submit-queue (batch tested with PRs 63322, 64718, 64708, 64775, 64777). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
Fix kubeadm for v1alpha1 configs
Signed-off-by: Chuck Ha <ha.chuck@gmail.com>
**What this PR does / why we need it**:
This PR allows v1alpha1 configurations to still work when running `kubeadm init`.
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixeskubernetes/kubeadm#884
**Special notes for your reviewer**:
```release-note
NONE
```
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kubeadm lowercases all domain names passed as additional SANs
**What this PR does / why we need it**:
Some domains, like ELBs, output a domain name with uppercase letters. To
accept these, we lowercase all arguments passed to ----apiserver-cert-extra-sans
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes #[kubeadm/827](https://github.com/kubernetes/kubeadm/issues/827)
```release-note
NONE
```
Some domains, like ELBs, output a domain name with uppercase letters. To
accept these, we lowercase all arguments passed to ----apiserver-cert-extra-sans
Automatic merge from submit-queue (batch tested with PRs 63453, 64592, 64482, 64618, 64661). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
Replace glog.Info{f,ln} with fmt.Print{f,ln}
Please see commit message.
Signed-off-by: Chuck Ha <ha.chuck@gmail.com>
**What this PR does / why we need it**:
This PR makes kubeadm's logging output consistent for the regular case and offers verbosity with glog.
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixeskubernetes/kubeadm#852
**Special notes for your reviewer**:
Unfortunately there is one call site in a dependency that uses a bare glog.Infof which we can't change without a bigger effort.
**Release note**:
```release-note
NONE
```
This follows the pattern `kubectl` uses for logging.
There are two remaining glog.Infof call that cannot be removed easily.
One glog call comes from kubelet validation which calls features.SetFromMap.
The other comes from test/e2e during kernel validation.
Mostly fixeskubernetes/kubeadm#852
Signed-off-by: Chuck Ha <ha.chuck@gmail.com>
Automatic merge from submit-queue (batch tested with PRs 64057, 63223, 64346, 64562, 64408). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
kubeadm: Refactor the Bootstrap Tokens usage in the API types
**What this PR does / why we need it**:
This PR:
- Moves some common, generic Bootstrap Token helpers and constants from `k8s.io/kubernetes/cmd/kubeadm/app/util/token` to `k8s.io/client-go/tools/bootstrap/token/`
- Breaks out the top-level Bootstrap Token fields to a dedicated `BootstrapToken` struct with helper functions.
- Instead of representing the Bootstrap Token as a plain `string`, there is now a wrapper struct `BootstrapTokenString` that can marshal/unmarshal correctly and supports validation on create, and splitting up the full token in the ID/Secret parts automatically.
- Makes kubeadm support multiple Bootstrap Tokens automatically by supporting a slice of `BootstrapToken` in the `MasterConfiguration` API object
- Consolidates the place for kubeadm to create token-related flags in an `options` package
- Supports automatic conversion from the `v1alpha1` to `v1alpha2` API
- Adds support to set token expiration directly instead of setting a TTL (Expiration and TTL are mutually exclusive)
- Removes the old `TokenDiscovery` struct we're not using anymore inside of kubeadm
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Related to https://github.com/kubernetes/community/pull/2131
**Special notes for your reviewer**:
This is work in progress. Please only review the first two commits for now.
I will work on splitting up this PR in smaller chunks.
I will also write unit tests tomorrow.
**Release note**:
```release-note
[action required] kubeadm: The Token-related fields in the `MasterConfiguration` object have now been refactored. Instead of the top-level `.Token`, `.TokenTTL`, `.TokenUsages`, `.TokenGroups` fields, there is now a `BootstrapTokens` slice of `BootstrapToken` objects that support the same features under the `.Token`, `.TTL`, `.Usages`, `.Groups` fields.
```
@kubernetes/sig-cluster-lifecycle-pr-reviews @mattmoyer @liztio
Automatic merge from submit-queue (batch tested with PRs 63348, 63839, 63143, 64447, 64567). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
Move pkg/scheduler/schedulercache -> pkg/scheduler/cache
**What this PR does / why we need it**:
Move pkg/scheduler/schedulercache -> pkg/scheduler/cache
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes#63813
**Special notes for your reviewer**:
In order to prevent name conflicts still rename the `cache` to `schedulercache`.
**Release note**:
```release-note
NONE
```
Automatic merge from submit-queue (batch tested with PRs 64605, 64570). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
Version mismatch is now a skippable error
**What this PR does / why we need it**:
Previously, kubeadm enforced the same major and minor versions as the version of kubernetes it was installing. This is still enforced by default, but now the `--force` flag can override it. This is useful for testing and other edge cases.
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes #[kubeadm/877](https://github.com/kubernetes/kubeadm/issues/877)
**Special notes for your reviewer**:
**Release note**:
```release-note
kubeadm upgrade apply can now ignore version errors with --force
```
Automatic merge from submit-queue (batch tested with PRs 62460, 64480, 63774, 64540, 64337). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
Save kubeadm manifest backup directories
**What this PR does / why we need it**:
Kubeadm will now preserves previous manifests after `kubeadm upgrade apply`. Previously these files would be deleted after the upgrade succeeded
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes # [kubeadm/489](https://github.com/kubernetes/kubeadm/issues/489)
**Special notes for your reviewer**:
**Release note**:
```release-note
kubeadm now preserves previous manifests after upgrades
```
Automatic merge from submit-queue (batch tested with PRs 62460, 64480, 63774, 64540, 64337). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
kubeadm uses its own scheme instead of kubectl scheme
**What this PR does / why we need it**:
kubeadm uses its own scheme instead of kubectl scheme
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes #
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
remove unused code in kubeadm error.go
**What this PR does / why we need it**:
remove unused code in kubeadm error.go
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes #
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
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.
Automatic merge from submit-queue (batch tested with PRs 64338, 64219, 64486, 64495, 64347). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
kubeadm: conditionally set the kubelet cgroup driver for Docker
**What this PR does / why we need it**:
Add a new utility file - util/cgroupdriver.go.
Currently it only contains the public function GetCgroupDriverDocker().
The function uses 'docker info' to obtain the cgroup driver
for Docker.
On a later stage this file can contain more methods for different
CRI.
Use GetCgroupDriverDocker() in phases/kubelet/flags.go
to conditionally set the 'cgroup-driver' argument. On error
print a warning and don't set the argument value.
Add unit tests in cgroupdriver_test.go.
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixeskubernetes/kubeadm#844
**Special notes for your reviewer**:
NONE
**Release note**:
```release-note
kubeadm: conditionally set the kubelet cgroup driver for Docker
```
/area kubeadm
/kind enhancement
@kubernetes/sig-cluster-lifecycle-pr-reviews
@luxas
Automatic merge from submit-queue (batch tested with PRs 57082, 64325, 64016, 64443, 64403). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
remove CrictlChecker from preflight checks
**What this PR does / why we need it**:
CrictlChecker uses InPathCheck to check if crictl presents
in the PATH. The same check is done in CRICheck function.
CrictlChecker is also called unconditionally, producing messages
that can confuse users. CRICheck is called only when needed, i.e.
when user specifies CRI socket.
**Release note**:
```release-note
NONE
```
Automatic merge from submit-queue (batch tested with PRs 61803, 64305, 64170, 64361, 64339). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
Remove some unnecessarily gendered pronouns in comments
**What this PR does / why we need it**:
A bunch of comments are unnecessarily gendered. I've changed them to gender-neutral they/theirs.
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
Automatic merge from submit-queue (batch tested with PRs 61803, 64305, 64170, 64361, 64339). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
Improve the help of kubeadm completion
**What this PR does / why we need it**:
Add note that 'bash-completion' is required on Linux too.
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes [kubernetes/kubeadm/#860](https://github.com/kubernetes/kubeadm/issues/860)
**Special notes for your reviewer**:
cc @neolit123
**Release note**:
```release-note
NONE
```
Automatic merge from submit-queue (batch tested with PRs 64318, 64269, 64438, 64516, 64311). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
UX improvement for preflight check for external etcd client certificates
**What this PR does / why we need it**:
UX improvement for preflight check for external etcd client certificates
By using same preflight check label for all etcd client certificates, it will
allow user to use single identifier, and as result shorter command line
arguments to kubeadm, in case multiple issues found with those files.
Fixes:
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixeskubernetes/kubeadm#834
**Special notes for your reviewer**:
**Release note**:
```release-note
Label ExternalEtcdClientCertificates can be used for ignoring all preflight check issues related to client certificate files for external etcd.
```
Add a new utility file - util/cgroupdriver.go.
Currently it only contains the public function GetCgroupDriverDocker().
The function uses 'docker info' to obtain the cgroup driver
for Docker.
On a later stage this file can contain more methods for different
CRI.
Use GetCgroupDriverDocker() in phases/kubelet/flags.go
to conditionally set the 'cgroup-driver' argument. On error
print a warning and don't set the argument value.
Add unit tests in cgroupdriver_test.go.
Automatic merge from submit-queue (batch tested with PRs 64322, 64210, 64458, 64232, 64370). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
kubeadm: Add a 'kubeadm config migrate' command
**What this PR does / why we need it**:
This is an UX improvement so users may easier "upgrade" their **configuration files** from the an old version (e.g. `v1alpha1`) version to a new one (e.g. `v1alpha2`), can do this **locally and seamlessly without touching a cluster**. We talked about this in the SIG meeting; getting the users to be able to convert their checked-in configuration files to new API versions will be crucial.
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes #
**Special notes for your reviewer**:
**Release note**:
```release-note
kubeadm: Add a 'kubeadm config migrate' command to convert old API types to their newer counterparts in the new, supported API types. This is just a client-side tool, it just executes locally without requiring a cluster to be running. You can think about this as an Unix pipe that upgrades config files.
```
@kubernetes/sig-cluster-lifecycle-pr-reviews @liztio
Automatic merge from submit-queue (batch tested with PRs 64322, 64210, 64458, 64232, 64370). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
kubeadm: Move .NodeName and .CRISocket to a common sub-struct
**What this PR does / why we need it**:
Regroups some common fields for `kubeadm init` and `kubeadm join` only used for the initial node registration.
Lets the user specify ExtraArgs to the kubelet.
Now also runs the dynamic env file creation for `kubeadm join`.
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes https://github.com/kubernetes/kubeadm/issues/847
Follows-up https://github.com/kubernetes/kubernetes/pull/63887
Related to kubernetes/kubeadm#822
**Special notes for your reviewer**: WIP, but please review so we can finalize the direction of the PR
**Release note**:
```release-note
[action required] `.NodeName` and `.CRISocket` in the `MasterConfiguration` and `NodeConfiguration` v1alpha1 API objects are now `.NodeRegistration.Name` and `.NodeRegistration.CRISocket` respectively in the v1alpha2 API. The `.NoTaintMaster` field has been removed in the v1alpha2 API.
```
@kubernetes/sig-cluster-lifecycle-pr-reviews @liztio
Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
fix parsing 'crictl pods -q' output
**What this PR does / why we need it**:
fix parsing 'crictl pods -q' output
Output of crictl pods -q is a list of running pod ids, one id per line.
Current code splits this output incorrectly which makes next command
'crictl stopp' fail if there is more than one pod running.
Should be fixed by using strings.Fields instead of strings.Split.
**Release note**:
```release-note
NONE
```
Automatic merge from submit-queue (batch tested with PRs 64258, 63068). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
Update the CoreDNS version and manifest
**What this PR does / why we need it**:
Bumps CoreDNS to 1.1.3 and updates manifest
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes #
**Special notes for your reviewer**:
**Release note**:
```release-note
CoreDNS is now v1.1.3
```
Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
kubeadm: Pull images early in `kubeadm init` by default
kubeadm now pulls container images before the init step.
* This commit also fixes a dependency cycle
**What this PR does / why we need it**:
This PR adds a check to kubeadm preflight checks that pulls images down before kubeadm tries to run them so boot up time of containers does not have to pull.
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixeskubernetes/kubeadm#825
**Special notes for your reviewer**:
The interface stuff is to remove a dependency cycle where utils pulled in preflight and preflight pulled in utils. I do not think this utils package should be importing preflight.
**Release note**:
```release-note
kubeadm will pull required images during preflight checks if it cannot find them on the system
```
