Most of these could have been refactored automatically but it wouldn't
have been uglier. The unsophisticated tooling left lots of unnecessary
struct -> pointer -> struct transitions.
CreateOrMutateConfigMap was not resilient when it was trying to Create
the ConfigMap. If this operation returned an unknown error the whole
operation would fail, because it was strict in what error it was
expecting right afterwards: if the error returned by the Create call
was a IsAlreadyExists error, it would work fine. However, if an
unexpected error (such as an EOF) happened, this call would fail.
We are seeing this error specially when running control plane node
joins in an automated fashion, where things happen at a relatively
high speed pace.
It was specially easy to reproduce with kind, with several control
plane instances. E.g.:
```
[upload-config] Storing the configuration used in ConfigMap "kubeadm-config" in the "kube-system" Namespace
I1130 11:43:42.788952 887 round_trippers.go:443] POST https://172.17.0.2:6443/api/v1/namespaces/kube-system/configmaps?timeout=10s in 1013 milliseconds
Post https://172.17.0.2:6443/api/v1/namespaces/kube-system/configmaps?timeout=10s: unexpected EOF
unable to create ConfigMap
k8s.io/kubernetes/cmd/kubeadm/app/util/apiclient.CreateOrMutateConfigMap
/go/src/k8s.io/kubernetes/_output/dockerized/go/src/k8s.io/kubernetes/cmd/kubeadm/app/util/apiclient/idempotency.go:65
```
This change makes this logic more resilient to unknown errors. It will
retry on the light of unknown errors until some of the expected error
happens: either `IsAlreadyExists`, in which case we will mutate the
ConfigMap, or no error, in which case the ConfigMap has been created.
There are two writes yet only one read on a non-buffered channel that is
created locally and not passed anywhere else.
Therefore, it could leak one of its two spawned Goroutines if either:
* The provided `f` takes longer than an erroneous result from
`waiter.WaitForHealthyKubelet`, or;
* The provided `f` completes before an erroneous result from
`waiter.WaitForHealthyKubelet`.
The fix is to add a one-element buffer so that the channel write happens
for the second Goroutine in these cases, allowing it to finish and freeing
references to the now-buffered channel, letting it to be GC'd.
During the control plane joins, sometimes the control plane returns an
expected error when trying to download the `kubeadm-config` ConfigMap.
This is a workaround for this issue until the root cause is completely
identified and fixed.
Ideally, this commit should be reverted in the near future.
* fix duplicated imports of api/core/v1
* fix duplicated imports of client-go/kubernetes
* fix duplicated imports of rest code
* change import name to more reasonable
Add the functionality to support `CreateOrMutateConfigMap` and `MutateConfigMap`.
* `CreateOrMutateConfigMap` will try to create a given ConfigMap object; if this ConfigMap
already exists, a new version of the resource will be retrieved from the server and a
mutator callback will be called on it. Then, an `Update` of the mutated object will be
performed. If there's a conflict during this `Update` operation, retry until no conflict
happens. On every retry the object is refreshed from the server to the latest version.
* `MutateConfigMap` will try to get the latest version of the ConfigMap from the server,
call the mutator callback and then try to `Update` the mutated object. If there's a
conflict during this `Update` operation, retry until no conflict happens. On every retry
the object is refreshed from the server to the latest version.
Add unit tests for `MutateConfigMap`
* One test checks that in case of no conflicts, the update of the
given ConfigMap happens without any issues.
* Another test mimics 5 consecutive CONFLICT responses when updating
the given ConfigMap, whereas the sixth try it will work.
- move most unrelated to phases output to klog.V(1)
- rename some prefixes for consistency - e.g.
[kubelet] -> [kubelet-start]
- control-plane-prepare: print details for each generated CP
component manifest.
- uppercase the info text for all "[reset].." lines
- modify the text for one line in reset
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 functions in cmd
**What this PR does / why we need it**:
/kind cleanup
**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 (batch tested with PRs 55511, 63372, 63400, 63100, 63769). 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 kubeadm upgrade path for CoreDNS
**What this PR does / why we need it**:
This PR achieves the following:
1. Retains the CoreDNS ConfigMap defined by the user during `kubeadm upgrade`.
2. Removes the CoreDNS deployment when user decides to install kube-dns during `kubeadm upgrade`.
**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 (batch tested with PRs 62655, 61711, 59122, 62853, 62390). 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>.
Modify the kubeadm upgrade DAG for the TLS Upgrade
**What this PR does / why we need it**:
This adds the necessary utilities to detect Etcd TLS on static pods from the file system and query Etcd.
It modifies the upgrade logic to make it support the APIServer downtime.
Tests are included and should be passing.
```bash
bazel test //cmd/kubeadm/... \
&& bazel build //cmd/kubeadm --platforms=@io_bazel_rules_go//go/toolchain:linux_amd64 \
&& issue=TLSUpgrade ~/Repos/vagrant-kubeadm-testing/copy_kubeadm_bin.sh
```
These cases are working consistently for me
```bash
kubeadm-1.9.6 reset \
&& kubeadm-1.9.6 init --kubernetes-version 1.9.1 \
&& kubectl apply -f https://git.io/weave-kube-1.6
/vagrant/bin/TLSUpgrade_kubeadm upgrade apply 1.9.6 # non-TLS to TLS
/vagrant/bin/TLSUpgrade_kubeadm upgrade apply 1.10.0 # TLS to TLS
/vagrant/bin/TLSUpgrade_kubeadm upgrade apply 1.10.1 # TLS to TLS
/vagrant/bin/TLSUpgrade_kubeadm upgrade apply 1.9.1 # TLS to TLS /w major version downgrade
```
This branch is based on top of #61942, as resolving the hash race condition is necessary for consistent behavior.
It looks to fit in pretty well with @craigtracey's PR: #62141
The interfaces are pretty similar
/assign @detiber @timothysc
**Which issue(s) this PR fixes**
Helps with https://github.com/kubernetes/kubeadm/issues/740
**Special notes for your reviewer**:
278b322a1c
[kubeadm] Implement ReadStaticPodFromDisk
c74b56372d
Implement etcdutils with Cluster.HasTLS()
- Test HasTLS()
- Instrument throughout upgrade plan and apply
- Update plan_test and apply_test to use new fake Cluster interfaces
- Add descriptions to upgrade range test
- Support KubernetesDir and EtcdDataDir in upgrade tests
- Cover etcdUpgrade in upgrade tests
- Cover upcoming TLSUpgrade in upgrade tests
8d8e5fe33b
Update test-case, fix nil-pointer bug, and improve error message
97117fa873
Modify the kubeadm upgrade DAG for the TLS Upgrade
- Calculate `beforePodHashMap` before the etcd upgrade in anticipation of
KubeAPIServer downtime
- Detect if pre-upgrade etcd static pod cluster `HasTLS()==false` to switch
on the Etcd TLS Upgrade if TLS Upgrade:
- Skip L7 Etcd check (could implement a waiter for this)
- Skip data rollback on etcd upgrade failure due to lack of L7 check
(APIServer is already down unable to serve new requests)
- On APIServer upgrade failure, also rollback the etcd manifest to
maintain protocol compatibility
- Add logging
**Release note**:
```release-note
kubeadm upgrade no longer races leading to unexpected upgrade behavior on pod restarts
kubeadm upgrade now successfully upgrades etcd and the controlplane to use TLS
kubeadm upgrade now supports external etcd setups
kubeadm upgrade can now rollback and restore etcd after an upgrade failure
```
