Automatic merge from submit-queue (batch tested with PRs 41919, 41149, 42350, 42351, 42285)
enable cgroups tiers and node allocatable enforcement on pods by default.
```release-note
Pods are launched in a separate cgroup hierarchy than system services.
```
Depends on #41753
cc @derekwaynecarr
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
```
Automatic merge from submit-queue
Switch resourcequota controller to shared informers
Originally part of #40097
I have had some issues with this change in the past, when I updated `pkg/quota` to use the new informers while `pkg/controller/resourcequota` remained on the old informers. In this PR, both are switched to using the new informers. The issues in the past were lots of flakey test failures in the ResourceQuota e2es, where it would randomly fail to see deletions and handle replenishment. I am hoping that now that everything here is consistently using the new informers, there won't be any more of these flakes, but it's something to keep an eye out for.
I also think `pkg/controller/resourcequota` could be cleaned up. I don't think there's really any need for `replenishment_controller.go` any more since it's no longer running individual controllers per kind to replenish. It instead just uses the shared informer and adds event handlers to it. But maybe we do that in a follow up.
cc @derekwaynecarr @smarterclayton @wojtek-t @deads2k @sttts @liggitt @timothysc @kubernetes/sig-scalability-pr-reviews
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 (batch tested with PRs 40251, 40171)
Mark --docker-exec-handler deprecated
We plan to drop support for the nsenter exec handler in the future. Marking this flag as deprecated to warn the users.
Automatic merge from submit-queue
Kubelet: Fix the description of MaxContainers kubelet flag.
Found this during code review.
The default number has been changed to `-1` and `1`. 82c488bd6e/pkg/apis/componentconfig/v1alpha1/defaults.go (L279-L285)
@yujuhong
/cc @saad-ali This PR fixed incorrect doc.
Provides an opt-in flag, --experimental-fail-swap-on (and corresponding
KubeletConfiguration value, ExperimentalFailSwapOn), which is false by default.
In order to be able to use new mounter library, this PR adds the
mounterPath flag to kubelet which passes the flag to the mount
interface. If flag is empty, mount uses default mount path.
Automatic merge from submit-queue
WIP: Remove the legacy networking mode
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**What this PR does / why we need it**:
Removes the deprecated configure-cbr0 flag and networking mode to avoid having untested and maybe unstable code in kubelet, see: #33789
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, #<issue_number>, ...)` format, will close that issue when PR gets merged)*:
fixes#30589fixes#31937
**Special notes for your reviewer**: There are a lot of deployments who rely on this networking mode. Not sure how we deal with that: force switch to kubenet or just delete the old deployment?
But please review the code changes first (the first commit)
**Release note**:
<!-- Steps to write your release note:
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2. Enter your extended release note in the below block; leaving it blank means using the PR title as the release note. If no release note is required, just write `NONE`.
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```release-note
Removed the deprecated kubelet --configure-cbr0 flag, and with that the "classic" networking mode as well
```
PTAL @kubernetes/sig-network @kubernetes/sig-node @mikedanese
