rktnetes is not a CRI implementation, and does not provide runtime
conditions. This change fixes the issue where rkt will never be
considered running from kubelet's point of view.
Make the location of dockershim.sock configurable, so downstream
projects (such as OpenShift) can place it in a location that does not
require root access (e.g. for integration tests).
Make the kubelet respect and use the values of
--container-runtime-endpoint and --image-service-endpoint, if set. If
unset, the default value of /var/run/dockershim.sock is used.
Automatic merge from submit-queue
Clearer ImageGC failure errors. Fewer events.
Addresses #26000. Kubelet often "fails" image garbage collection if cAdvisor has not completed the first round of stats collection. Don't create events for a single failure, and make log messages more specific.
@kubernetes/sig-node-bugs
Kubelet flags are not necessarily appropriate for the KubeletConfiguration
object. For example, this PR also removes HostnameOverride and NodeIP
from KubeletConfiguration. This is a preleminary step to enabling Nodes
to share configurations, as part of the dynamic Kubelet configuration
feature (#29459). Fields that must be unique for each node inhibit
sharing, because their values, by definition, cannot be shared.
Automatic merge from submit-queue
[Bug] Fix gpu initialization in Kubelet
Kubelet incorrectly fails if `AllAlpha=true` feature gate is enabled with container runtimes that are not `docker`.
Replaces #42407
Automatic merge from submit-queue (batch tested with PRs 41931, 39821, 41841, 42197, 42195)
Use `docker logs` directly if the docker logging driver is not `json-file`
Fixes https://github.com/kubernetes/kubernetes/issues/41996.
Post the PR first, I still need to manually test this, because we don't have test coverage for journald logging pluggin.
@yujuhong @dchen1107
/cc @kubernetes/sig-node-pr-reviews
Introduced chages:
1. Re-writing of the resolv.conf file generated by docker.
Cluster dns settings aren't passed anymore to docker api in all cases, not only for pods with host network:
the resolver conf will be overwritten after infra-container creation to override docker's behaviour.
2. Added new one dnsPolicy - 'ClusterFirstWithHostNet', so now there are:
- ClusterFirstWithHostNet - use dns settings in all cases, i.e. with hostNet=true as well
- ClusterFirst - use dns settings unless hostNetwork is true
- Default
Fixes#17406
Automatic merge from submit-queue
Extend experimental support to multiple Nvidia GPUs
Extended from #28216
```release-note
`--experimental-nvidia-gpus` flag is **replaced** by `Accelerators` alpha feature gate along with support for multiple Nvidia GPUs.
To use GPUs, pass `Accelerators=true` as part of `--feature-gates` flag.
Works only with Docker runtime.
```
1. Automated testing for this PR is not possible since creation of clusters with GPUs isn't supported yet in GCP.
1. To test this PR locally, use the node e2e.
```shell
TEST_ARGS='--feature-gates=DynamicKubeletConfig=true' FOCUS=GPU SKIP="" make test-e2e-node
```
TODO:
- [x] Run manual tests
- [x] Add node e2e
- [x] Add unit tests for GPU manager (< 100% coverage)
- [ ] Add unit tests in kubelet package
Automatic merge from submit-queue (batch tested with PRs 41994, 41969, 41997, 40952, 40576)
Guaranteed admission for Critical Pods
This is the first step in implementing node-level preemption for critical pods.
It defines the AdmissionFailureHandler interface, which allows callers, like the kubelet, to define how failed predicates are handled, and take steps to correct failures if necessary.
In the kubelet's implementation, it triggers preemption if the pod being admitted is critical, and if the only failed predicates are InsufficientResourceErrors, then it prempts (not yet implemented) other other pods to allow admission of the critical pod.
cc: @vishh
Where possible, switch the scheduler to use generated listers and
informers. There are still some places where it probably makes more
sense to use one-off reflectors/informers (listing/watching just a
single node, listing/watching scheduled & unscheduled pods using a field
selector).
Automatic merge from submit-queue (batch tested with PRs 38101, 41431, 39606, 41569, 41509)
Report node not ready on failed PLEG health check
Report node not ready if PLEG health check fails.
Automatic merge from submit-queue (batch tested with PRs 38101, 41431, 39606, 41569, 41509)
optimize killPod() and syncPod() functions
make sure that one of the two arguments must be non-nil: runningPod, status ,just like the function note says
and judge the return value in syncPod() function before setting podKilled
Automatic merge from submit-queue (batch tested with PRs 41466, 41456, 41550, 41238, 41416)
Delay Deletion of a Pod until volumes are cleaned up
#41436 fixed the bug that caused #41095 and #40239 to have to be reverted. Now that the bug is fixed, this shouldn't cause problems.
@vishh @derekwaynecarr @sjenning @jingxu97 @kubernetes/sig-storage-misc
make sure that one of the two arguments must be non-nil: runningPod, status ,just like the function note says
and judge the return value in syncPod() function before setting podKilled
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.
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/
```
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.
- 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`).
Automatic merge from submit-queue (batch tested with PRs 39079, 38991, 38673)
Support systemd based pod qos in CRI dockershim
This PR makes pod level QoS works for CRI dockershim for systemd based cgroups. And will also fix#36807
- [x] Add cgroupDriver to dockerService and use docker info api to set value for it
- [x] Add a NOTE that detection only works for docker 1.11+, see [CHANGE LOG](https://github.com/docker/docker/blob/master/CHANGELOG.md#1110-2016-04-13)
- [x] Generate cgroupParent in syntax expected by cgroupDriver
- [x] Set cgroupParent to hostConfig for both sandbox and user container
- [x] Check if kubelet conflicts with cgroup driver of docker
cc @derekwaynecarr @vishh
Automatic merge from submit-queue (batch tested with PRs 38154, 38502)
Rename "release_1_5" clientset to just "clientset"
We used to keep multiple releases in the main repo. Now that [client-go](https://github.com/kubernetes/client-go) does the versioning, there is no need to keep releases in the main repo. This PR renames the "release_1_5" clientset to just "clientset", clientset development will be done in this directory.
@kubernetes/sig-api-machinery @deads2k
```release-note
The main repository does not keep multiple releases of clientsets anymore. Please find previous releases at https://github.com/kubernetes/client-go
```
Yu-Ju Hong