Automatic merge from submit-queue (batch tested with PRs 40796, 40878, 36033, 40838, 41210)
Implement TTL controller and use the ttl annotation attached to node in secret manager
For every secret attached to a pod as volume, Kubelet is trying to refresh it every sync period. Currently Kubelet has a ttl-cache of secrets of its pods and the ttl is set to 1 minute. That means that in large clusters we are targetting (5k nodes, 30pods/node), given that each pod has a secret associated with ServiceAccount from its namespaces, and with large enough number of namespaces (where on each node (almost) every pod is from a different namespace), that resource in ~30 GETs to refresh all secrets every minute from one node, which gives ~2500QPS for GET secrets to apiserver.
Apiserver cannot keep up with it very easily.
Desired solution would be to watch for secret changes, but because of security we don't want a node watching for all secrets, and it is not possible for now to watch only for secrets attached to pods from my node.
So as a temporary solution, we are introducing an annotation that would be a suggestion for kubelet for the TTL of secrets in the cache and a very simple controller that would be setting this annotation based on the cluster size (the large cluster is, the bigger ttl is).
That workaround mean that only very local changes are needed in Kubelet, we are creating a well separated very simple controller, and once watching "my secrets" will be possible it will be easy to remove it and switch to that. And it will allow us to reach scalability goals.
@dchen1107 @thockin @liggitt
Automatic merge from submit-queue (batch tested with PRs 40873, 40948, 39580, 41065, 40815)
[CRI] Enable Hostport Feature for Dockershim
Commits:
1. Refactor common hostport util logics and add more tests
2. Add HostportManager which can ADD/DEL hostports instead of a complete sync.
3. Add Interface for retreiving portMappings information of a pod in Network Host interface.
Implement GetPodPortMappings interface in dockerService.
4. Teach kubenet to use HostportManager
Automatic merge from submit-queue (batch tested with PRs 41103, 41042, 41097, 40946, 40770)
Use Clientset interface in KubeletDeps
**What this PR does / why we need it**:
This replaces the Clientset struct with the equivalent interface for the KubeClient injected via KubeletDeps. This is useful for testing and for accessing the Node and Pod status event stream without an API server.
**Special notes for your reviewer**:
Follow up to #4907
**Release note**:
`NONE`
Automatic merge from submit-queue (batch tested with PRs 40289, 40877, 40879, 39972, 40942)
Rename experimental-cgroups-per-pod flag
**What this PR does / why we need it**:
1. Rename `experimental-cgroups-per-qos` to `cgroups-per-qos`
1. Update hack/local-up-cluster to match `CGROUP_DRIVER` with docker runtime if used.
**Special notes for your reviewer**:
We plan to roll this feature out in the upcoming release. Previous node e2e runs were running with this feature on by default. We will default this feature on for all e2es next week.
**Release note**:
```release-note
Rename --experiemental-cgroups-per-qos to --cgroups-per-qos
```
Automatic merge from submit-queue
Optionally avoid evicting critical pods in kubelet
For #40573
```release-note
When feature gate "ExperimentalCriticalPodAnnotation" is set, Kubelet will avoid evicting pods in "kube-system" namespace that contains a special annotation - `scheduler.alpha.kubernetes.io/critical-pod`
This feature should be used in conjunction with the rescheduler to guarantee availability for critical system pods - https://kubernetes.io/docs/admin/rescheduler/
```
- split out port forwarding into its own package
Allow multiple port forwarding ports
- Make it easy to determine which port is tied to which channel
- odd channels are for data
- even channels are for errors
- allow comma separated ports to specify multiple ports
Add portfowardtester 1.2 to whitelist
Automatic merge from submit-queue (batch tested with PRs 40232, 40235, 40237, 40240)
move listers out of cache to reduce import tree
Moving the listers from `pkg/client/cache` snips links to all the different API groups from `pkg/storage`, but the dreaded `ListOptions` remains.
@sttts
Automatic merge from submit-queue (batch tested with PRs 37228, 40146, 40075, 38789, 40189)
kubelet: storage: teardown terminated pod volumes
This is a continuation of the work done in https://github.com/kubernetes/kubernetes/pull/36779
There really is no reason to keep volumes for terminated pods attached on the node. This PR extends the removal of volumes on the node from memory-backed (the current policy) to all volumes.
@pmorie raised a concern an impact debugging volume related issues if terminated pod volumes are removed. To address this issue, the PR adds a `--keep-terminated-pod-volumes` flag the kubelet and sets it for `hack/local-up-cluster.sh`.
For consideration in 1.6.
Fixes#35406
@derekwaynecarr @vishh @dashpole
```release-note
kubelet tears down pod volumes on pod termination rather than pod deletion
```
Automatic merge from submit-queue (batch tested with PRs 40168, 40165, 39158, 39966, 40190)
dockershim: add support for the 'nsenter' exec handler
This change simply plumbs the kubelet configuration
(--docker-exec-handler) to DockerService.
This fixes#35747.
- exclude duplicates while merging of host's and dns' search lines to form pod's one
- truncate pod's search line if it exceeds resolver limits: is > 255 chars and containes > 6 searches
- monitoring the resolv.conf file which is used by kubelet (set thru --resolv-conf="") and logging and eventing if search line in it consists of more than 3 entries
(or 6 if Cluster Domain is set) or its lenght is > 255 chars
- logging and eventing when a pod's search line is > 255 chars or containes > 6 searches during forming
Fixes#29270
Automatic merge from submit-queue
kubelet: remove the pleg health check from healthz
This prevents kubelet from being killed when docker hangs.
Also, kubelet will report node not ready if PLEG hangs (`docker ps` + `docker inspect`).
