Automatic merge from submit-queue
Allow multipe DNS servers as comma-seperated argument for kubelet --dns
This PR explores how kubectls "--dns" could be extended to specify multiple DNS servers for in-cluster PODs. Testing on the local libvirt-coreos cluster shows that multiple DNS server are injected without issues.
Specifying multiple DNS servers increases resilience against
- Packet drops
- Single server failure
I am debugging services that do 50+ DNS requests for a single incoming interactive request, thus highly increase the chance of a slowdown (+5s) due to a single packet drop. Switching to two DNS servers will reduce the impact of the issues (roughly +1s on glibc, 0s on musl, error-rate goes down to error-rate^2).
Note that there is no need to change any runtime related code as far as I know. In the case of "default" dns the /etc/resolv.conf is parsed and multiple DNS server are send to the backend anyway. This only adds the same capability for the clusterFirst case.
I've heard from @thockin that multiple DNS entries are somehow considered. I've no idea what was considered, though. This is what I would like to see for our production use, though.
```release-note
NONE
```
This change makes kubelet to use the CRI implementation by default,
unless the users opt out explicitly by using --enable-cri=false.
For the rkt integration, the --enable-cri flag will have no effect
since rktnetes does not use CRI.
Also, mark the original --experimental-cri flag hidden and deprecated,
so that we can remove it in the next release.
Depending on an exact cluster setup multiple dns may make sense.
Comma-seperated lists of DNS server are quite common as DNS servers
are always plain IPs.
Automatic merge from submit-queue
Remove proxy-mode annotation from kube-proxy
**What this PR does / why we need it**:
This removes the net.experimental.kubernetes.io/proxy-mode and net.beta.kubernetes.io/proxy-mode annotations from kube-proxy.
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes#40582
**Special notes for your reviewer**:
**Release note**:
```release-note
Remove outdated net.experimental.kubernetes.io/proxy-mode and net.beta.kubernetes.io/proxy-mode annotations from kube-proxy.
```
Automatic merge from submit-queue (batch tested with PRs 39469, 40557)
Forgiveness api changes
**What this PR does / why we need it**:
Splited from #34825 , contains api changes that are needed to implement forgiveness:
1. update toleration api types to support forgiveness, added a new field forgivenessSeconds to indicate the duration of time it tolerates a taint.
2. update taint api types, added a new field to indicate the time the taint is added.
**Which issue this PR fixes** :
Related issue: #1574
Related PR: #34825
**Special notes for your reviewer**:
**Release note**:
```release-note
forgiveness alpha version api definition
```
Automatic merge from submit-queue (batch tested with PRs 39466, 39490, 39527)
bump gengo to latest
bumping gengo to limit surprises while working on https://github.com/kubernetes/kubernetes/pull/39475
@kubernetes/sig-api-machinery-misc
Automatic merge from submit-queue (batch tested with PRs 39351, 39322)
Remove the deprecated --reconcile-cidr flag from kubelet
**What this PR does / why we need it**:
Removes the `--reconcile-cidr` flag that has been deprecated since v1.5
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #
**Special notes for your reviewer**:
**Release note**:
```release-note
The `--reconcile-cidr` kubelet flag was removed since it had been deprecated since v1.5
```
@thockin
Automatic merge from submit-queue (batch tested with PRs 36263, 36755, 37357, 37222, 37524)
Add flag to enable contention profiling in scheduler.
```release-note
Add flag to enable contention profiling in scheduler.
```
Automatic merge from submit-queue
Fix default Seccomp profile directory
Looks like some of the refactoring caused us to lose the default
directory. Setting that explicitly here.
Fixes#36350
Provides an opt-in flag, --experimental-fail-swap-on (and corresponding
KubeletConfiguration value, ExperimentalFailSwapOn), which is false by default.
Automatic merge from submit-queue
Rename experimental-runtime-integration-type to experimental-cri
Also rename the field in the component config to `EnableCRI`
Automatic merge from submit-queue
Initial work on running windows containers on Kubernetes
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This is the first stab at getting the Kubelet running on Windows (fixes#30279), and getting it to deploy network-accessible pods that consist of Windows containers. Thanks @csrwng, @jbhurat for helping out.
The main challenge with Windows containers at this point is that container networking is not supported. In other words, each container in the pod will get it's own IP address. For this reason, we had to make a couple of changes to the kubelet when it comes to setting the pod's IP in the Pod Status. Instead of using the infra-container's IP, we use the IP address of the first container.
Other approaches we investigated involved "disabling" the infra container, either conditionally on `runtime.GOOS` or having a separate windows-docker container runtime that re-implemented some of the methods (would require some refactoring to avoid maintainability nightmare).
Other changes:
- The default docker endpoint was removed. This results in the docker client using the default for the specific underlying OS.
More detailed documentation on how to setup the Windows kubelet can be found at https://docs.google.com/document/d/1IjwqpwuRdwcuWXuPSxP-uIz0eoJNfAJ9MWwfY20uH3Q.
cc: @ikester @brendandburns @jstarks
