Automatic merge from submit-queue
Optional configmaps and secrets
Allow configmaps and secrets for environment variables and volume sources to be optional
Implements approved proposal c9f881b7bb
Release note:
```release-note
Volumes and environment variables populated from ConfigMap and Secret objects can now tolerate the named source object or specific keys being missing, by adding `optional: true` to the volume or environment variable source specifications.
```
Automatic merge from submit-queue (batch tested with PRs 37228, 40146, 40075, 38789, 40189)
Cleanup temp dirs
So funny story my /tmp ran out of space running the unit tests so I am cleaning up all the temp dirs we create.
Automatic merge from submit-queue
kubelet bootstrap: start hostNetwork pods before we have PodCIDR
Network readiness was checked in the pod admission phase, but pods that
fail admission are not retried. Move the check to the pod start phase.
Issue #35409
Issue #35521
Automatic merge from submit-queue
Use strongly-typed types.NodeName for a node name
We had another bug where we confused the hostname with the NodeName.
Also, if we want to use different values for the Node.Name (which is
an important step for making installation easier), we need to keep
better control over this.
A tedious but mechanical commit therefore, to change all uses of the
node name to use types.NodeName
We had another bug where we confused the hostname with the NodeName.
To avoid this happening again, and to make the code more
self-documenting, we use types.NodeName (a typedef alias for string)
whenever we are referring to the Node.Name.
A tedious but mechanical commit therefore, to change all uses of the
node name to use types.NodeName
Also clean up some of the (many) places where the NodeName is referred
to as a hostname (not true on AWS), or an instanceID (not true on GCE),
etc.
Automatic merge from submit-queue
Fixed TODO: move predicate check into a pod admitter
refractoring AdmitPod func to move predicate check into a pod admitter
Switch most of the tests in this file to using the assert/require library
(in `github.com/stretchr/testify`) in the tests for better readability and
less code in general.
Automatic merge from submit-queue
Kubelet code move: volume / util
Addresses some odds and ends that I apparently missed earlier. Preparation for kubelet code-move ENDGAME.
cc @kubernetes/sig-node
MTU selection is difficult, and if there is a transport such as IPSEC in
use may be impossible. So we allow specification of the MTU with the
network-plugin-mtu flag, and we pass this down into the network
provider.
Currently implemented by kubenet.
The serviceAccountName is occasionally useful for clients running on
Kube that need to know who they are when talking to other components.
The nodeName is useful for PetSet or DaemonSet pods that need to make
calls back to the API to fetch info about their node.
Both fields are immutable, and cannot easily be retrieved in another
way.
Automatic merge from submit-queue
Always return command output for exec probes and kubelet RunInContainer
Always return command output for exec probes and kubelet RunInContainer, even if the command invocation returns nonzero.
When #24921 replaced RunInContainer with ExecInContainer, it introduced a change where an exec probe that failed no longer included the stdout/stderr from the probe in the event. For example, when running at log level 4, you see:
```
I0816 15:01:36.259826 29713 exec.go:38] Exec probe response: "Failed to access the status endpoint : HTTP Error 404: Not Found.\nHawkular metrics has only been running for 7\n seconds not aborting yet.\n"
```
But the event looks like this:
```
54s 22s 5 hawkular-metrics-hjme4 Pod spec.containers{hawkular-metrics} Warning Unhealthy {kubelet corbeau} Readiness probe failed:
```
Note the absence of the exec probe response after "Readiness probe failed". This PR restores the previous behavior.
cc @kubernetes/rh-cluster-infra @mwringe
xref https://github.com/openshift/origin/issues/10424
Automatic merge from submit-queue
Add volume reconstruct/cleanup logic in kubelet volume manager
Currently kubelet volume management works on the concept of desired
and actual world of states. The volume manager periodically compares the
two worlds and perform volume mount/unmount and/or attach/detach
operations. When kubelet restarts, the cache of those two worlds are
gone. Although desired world can be recovered through apiserver, actual
world can not be recovered which may cause some volumes cannot be cleaned
up if their information is deleted by apiserver. This change adds the
reconstruction of the actual world by reading the pod directories from
disk. The reconstructed volume information is added to both desired
world and actual world if it cannot be found in either world. The rest
logic would be as same as before, desired world populator may clean up
the volume entry if it is no longer in apiserver, and then volume
manager should invoke unmount to clean it up.
Fixes https://github.com/kubernetes/kubernetes/issues/27653
Currently kubelet volume management works on the concept of desired
and actual world of states. The volume manager periodically compares the
two worlds and perform volume mount/unmount and/or attach/detach
operations. When kubelet restarts, the cache of those two worlds are
gone. Although desired world can be recovered through apiserver, actual
world can not be recovered which may cause some volumes cannot be cleaned
up if their information is deleted by apiserver. This change adds the
reconstruction of the actual world by reading the pod directories from
disk. The reconstructed volume information is added to both desired
world and actual world if it cannot be found in either world. The rest
logic would be as same as before, desired world populator may clean up
the volume entry if it is no longer in apiserver, and then volume
manager should invoke unmount to clean it up.
Automatic merge from submit-queue
Support terminal resizing for exec/attach/run
```release-note
Add support for terminal resizing for exec, attach, and run. Note that for Docker, exec sessions
inherit the environment from the primary process, so if the container was created with tty=false,
that means the exec session's TERM variable will default to "dumb". Users can override this by
setting TERM=xterm (or whatever is appropriate) to get the correct "smart" terminal behavior.
```
Fixes#13585
Add support for terminal resizing for exec, attach, and run. Note that for Docker, exec sessions
inherit the environment from the primary process, so if the container was created with tty=false,
that means the exec session's TERM variable will default to "dumb". Users can override this by
setting TERM=xterm (or whatever is appropriate) to get the correct "smart" terminal behavior.
Automatic merge from submit-queue
Reorganize volume controllers and manager
* Move both PV and attach/detach volume controllers to `controllers/volume` (closes#26222)
* Rename `kubelet/volume` to `kubelet/volumemanager`
* Add/update OWNER files
Automatic merge from submit-queue
Volume manager must verify containers terminated before deleting for ungracefully terminated pods
A pod is removed from volume manager (triggering unmount) when it is deleted from the kubelet pod manager. Kubelet deletes the pod from pod manager as soon as it receives a delete pod request. As long as the graceful termination period is non-zero, this happens after kubelet has terminated all containers for the pod. However, when graceful termination period for a pod is set to zero, the volume is deleted from pod manager *before* its containers are terminated.
This can result in volumes getting unmounted from a pod before all containers have exited when graceful termination is set to zero.
This PR prevents that from happening by only deleting a volume from volume manager once it is deleted from the pod manager AND the kubelet containerRuntime status indicates all containers for the pod have exited. Because we do not want to call containerRuntime too frequently, we introduce a delay in the `findAndRemoveDeletedPods()` method to prevent it from executing more frequently than every two seconds.
Fixes https://github.com/kubernetes/kubernetes/issues/27691
Running test in tight loop to verify fix.
Ensure that kublet marks VolumeInUse before checking if it is Attached.
Also ensures that the attach/detach controller always fetches a fresh
copy of the node object before detach (instead ofKubelet relying on node
informer cache).
Automatic merge from submit-queue
Fix pkg/kubelet unit tests fail on OSX
use runtime.GOOS for the OperatingSystem and not hardcode it to linux.
Fixes#27730
Automatic merge from submit-queue
Kubelet can retrieve host IP even when apiserver has not been contacted
fixes https://github.com/kubernetes/kubernetes/issues/26590, fixes https://github.com/kubernetes/kubernetes/issues/6558
Right now the kubelet expects to get the hostIP from the kubelet's local nodeInfo cache. However, this will be empty if there is no api-server (or the apiServer has not yet been contacted).
In the case of static pods, this change means the downward api can now be used to populate hostIP.
Use the generic runtime method to get the netns path. Also
move reading the container IP address into cni (based off kubenet)
instead of having it in the Docker manager code. Both old and new
methods use nsenter and /sbin/ip and should be functionally
equivalent.
Modify attach/detach controller to keep track of volumes to report
attached in Node VolumeToAttach status.
Modify kubelet volume manager to wait for volume to show up in Node
VolumeToAttach status.
Implement exponential backoff for errors in volume manager and attach
detach controller
This commit adds a new volume manager in kubelet that synchronizes
volume mount/unmount (and attach/detach, if attach/detach controller
is not enabled).
This eliminates the race conditions between the pod creation loop
and the orphaned volumes loops. It also removes the unmount/detach
from the `syncPod()` path so volume clean up never blocks the
`syncPod` loop.
Automatic merge from submit-queue
kubelet/cadvisor: Refactor cadvisor disk stat/usage interfaces.
basically
1) cadvisor struct will know what runtime the kubelet is, passed in via additional argument to New()
2) rename cadvisor wrapper function to DockerImagesFsInfo() to ImagesFsInfo() and have linux implementation choose a label based on the runtime inside the cadvisor struct
2a) mock/fake/unsupported modified to take the same additional argument in New()
3) kubelet's wrapper for the cadvisor wrapper is renamed in parallel
4) make all tests use new interface
Automatic merge from submit-queue
Add support for PersistentVolumeClaim in Attacher/Detacher interface
The attach detach interface does not support volumes which are referenced through PVCs. This PR adds that support
Automatic merge from submit-queue
Only expose top N images in `NodeStatus`
Fix#25209
Sorted the image and only pick set top 50 sized images in node status.
cc @vishh
Automatic merge from submit-queue
Remove RunInContainer interface in Kubelet Runtime interface
According to #24689, we should merge RunInContainer and ExecInContainer in the container runtime interface.
@yujuhong @kubernetes/sig-node
Automatic merge from submit-queue
Automatically add node labels beta.kubernetes.io/{os,arch}
Proposal: #17981
As discussed in #22623:
> @davidopp: #9044 says cloud provider but can also cover platform stuff.
Adds a label `beta.kubernetes.io/platform` to `kubelet` that informs about the os/arch it's running on.
Makes it easy to specify `nodeSelectors` for different arches in multi-arch clusters.
```console
$ kubectl get no --show-labels
NAME STATUS AGE LABELS
127.0.0.1 Ready 1m beta.kubernetes.io/platform=linux-amd64,kubernetes.io/hostname=127.0.0.1
$ kubectl describe no
Name: 127.0.0.1
Labels: beta.kubernetes.io/platform=linux-amd64,kubernetes.io/hostname=127.0.0.1
CreationTimestamp: Thu, 31 Mar 2016 20:39:15 +0300
```
@davidopp @vishh @fgrzadkowski @thockin @wojtek-t @ixdy @bgrant0607 @dchen1107 @preillyme
Automatic merge from submit-queue
WIP v0 NVIDIA GPU support
```release-note
* Alpha support for scheduling pods on machines with NVIDIA GPUs whose kubelets use the `--experimental-nvidia-gpus` flag, using the alpha.kubernetes.io/nvidia-gpu resource
```
Implements part of #24071 for #23587
I am not familiar with the scheduler enough to know what to do with the scores. Mostly punting for now.
Missing items from the implementation plan: limitranger, rkt support, kubectl
support and docs
cc @erictune @davidopp @dchen1107 @vishh @Hui-Zhi @gopinatht
Implements part of #24071
I am not familiar with the scheduler enough to know what to do with the scores. Punting for now.
Missing items from the implementation plan: limitranger, rkt support, kubectl
support and user docs
Automatic merge from submit-queue
Abstract node side functionality of attachable plugins
- Create PhysicalAttacher interface to abstract MountDevice and
WaitForAttach.
- Create PhysicalDetacher interface to abstract WaitForDetach and
UnmountDevice.
- Expand unit tests to check that Attach, Detach, WaitForAttach,
WaitForDetach, MountDevice, and UnmountDevice get call where
appropriet.
Physical{Attacher,Detacher} are working titles suggestions welcome. Some other thoughts:
- NodeSideAttacher or NodeAttacher.
- AttachWatcher
- Call this Attacher and call the Current Attacher CloudAttacher.
- DeviceMounter (although there are way too many things called Mounter right now :/)
This is to address: https://github.com/kubernetes/kubernetes/pull/21709#issuecomment-192035382
@saad-ali
Automatic merge from submit-queue
Define interfaces for kubelet pod admission and eviction
There is too much code and logic in `kubelet.go` that makes it hard to test functions in discrete pieces.
I propose an interface that an internal module can implement that will let it make an admission decision for a pod. If folks are ok with the pattern, I want to move the a) predicate checking, b) out of disk, c) eviction preventing best-effort pods being admitted into their own dedicated handlers that would be easier for us to mock test. We can then just write tests to ensure that the `Kubelet` calls a call-out, and we can write easier unit tests to ensure that dedicated handlers do the right thing.
The second interface I propose was a `PodEvictor` that is invoked in the main kubelet sync loop to know if pods should be pro-actively evicted from the machine. The current active deadline check should move into a simple evictor implementation, and I want to plug the out of resource killer code path as an implementation of the same interface.
@vishh @timothysc - if you guys can ack on this, I will add some unit testing to ensure we do the call-outs.
/cc @kubernetes/sig-node @kubernetes/rh-cluster-infra
- Expand Attacher/Detacher interfaces to break up work more
explicitly.
- Add arguments to all functions to avoid having implementers store
the data needed for operations.
- Expand unit tests to check that Attach, Detach, WaitForAttach,
WaitForDetach, MountDevice, and UnmountDevice get call where
appropriet.
Automatic merge from submit-queue
Move predicates into library
This PR tries to implement #12744
Any suggestions/ideas are welcome. @davidopp
current state: integration test fails if including podCount check in Kubelet.
DONE:
1. refactor all predicates: predicates return fitOrNot(bool) and error(Error) in which the latter is of type PredicateFailureError or InsufficientResourceError
2. GeneralPredicates() is a predicate function, which includes serveral other predicate functions (PodFitsResource, PodFitsHost, PodFitsHostPort). It is registered as one of the predicates in DefaultAlgorithmProvider, and is also called in canAdmitPod() in Kubelet and should be called by other components (like rescheduler, etc if necessary. See discussion in issue #12744
TODO:
1. determine which predicates should be included in GeneralPredicates()
2. separate GeneralPredicates() into: a.) GeneralPredicatesEvictPod() and b.) GeneralPredicatesNotEvictPod()
3. DaemonSet should use GeneralPredicates()
DONE:
1. refactor all predicates: predicates return fitOrNot(bool) and error(Error) in which the latter is of type
PredicateFailureError or InsufficientResourceError. (For violation of either MaxEBSVolumeCount or
MaxGCEPDVolumeCount, returns one same error type as ErrMaxVolumeCountExceeded)
2. GeneralPredicates() is a predicate function, which includes serveral other predicate functions (PodFitsResource,
PodFitsHost, PodFitsHostPort). It is registered as one of the predicates in DefaultAlgorithmProvider, and
is also called in canAdmitPod() in Kubelet and should be called by other components (like rescheduler, etc)
if necessary. See discussion in issue #12744
3. remove podNumber check from GeneralPredicates
4. HostName is now verified in Kubelet's canAdminPod(). add TestHostNameConflicts in kubelet_test.go
5. add getNodeAnyWay() method in Kubelet to get node information in standaloneMode
TODO:
1. determine which predicates should be included in GeneralPredicates()
2. separate GeneralPredicates() into:
a. GeneralPredicatesEvictPod() and
b. GeneralPredicatesNotEvictPod()
3. DaemonSet should use GeneralPredicates()
Kubelet.cleanupOrphanedVolumes() compares list of volumes mounted to a node
with list of volumes that are required by pods scheduled on the node
("scheduled volume").
Both lists should contain real volumes, i.e. when a pod uses
PersistentVolumeClaim, the list must contain name of the bound volume instead
of name of the claim.
This change removes RuntimeCache in the pod workers and the syncPod() function.
Note that it doesn't deprecate RuntimeCache completely as other components
still rely on the cache.
Many users attempt to use 'kubectl logs' in order to find the logs
for a container, but receive no logs or an error telling them their
container is not running. The fix in this case is to run with '--previous',
but this does not match user expectations for the logs command.
This commit changes the behavior of the Kubelet to return the logs of
the currently running container or the previous running container unless
the user provides the "previous" flag. If the user specifies "follow"
the logs of the most recent container will be displayed, and if it is
a terminated container the logs will come to an end (the user can
repeatedly invoke 'kubectl logs --follow' and see the same output).
Clean up error messages in the kubelet log path to be consistent and
give users a more predictable experience.
Have the Kubelet return 400 on invalid requests
This updates the dockertools.dockerVersion to use a semantic versioning
library to more gracefully support engine versions which include
additional version fields.
Previously, go-dockerclient's APIVersion struct was use which only
handles plain numeric x.y.z version strings. With #19675, the library
was now used on the Docker engine string, however it is possible for the
engine string to include include additional information for beta, rc, or
distro specific builds.
This PR also enables the TestDockerRuntimeVersion test which was
previously just a FIXME and updates it to pass, and be used to test the
version string that cause #20005.
This negates the need for fsouza/go-dockerclient#451, since even with
that change, if a user was running Docker 1.10.0-rc1, this would cause
the kubelet to report it as simply 1.10.0.
- Ignore the "not found" error on deletion.
- Recognize the "already exists" error on creation and check if the existing
pod meets requirement. If so, don't report an error.
- Immediately create a mirror pod after a successful deletion, if needed.
This address a TODO when collecting the node version information so it
will properly report the configured runtime and its version. Previously,
this was hardcoded to "docker://" and the docker version, and would show
"docker://1.9.1" even when the kubelet was configured to use rkt.
With this change, it will use the runtime's Type() and Version() data.
This also changes the container.Runtime interface to add an APIVersion()
method. This can be used when the runtime has separate versions for the
engine and the API, such as with Docker. The Docker minimum version
validation has been updated to use APIVersion(), and
DockerManager.Version() now returns the engine version.
Add `kube-reserved` and `system-reserved` flags for configuration
reserved resources for usage outside of kubernetes pods. Allocatable is
provided by the Kubelet according to the formula:
```
Allocatable = Capacity - KubeReserved - SystemReserved
```
Also provides a method for estimating a reasonable default for
`KubeReserved`, but the current implementation probably is low and needs
more tuning.
Kubelet doesn't perform checkpointing and loses all its internal states after
restarts. It'd then mistaken pods from the api server as new pods and attempt
to go through the admission process. This may result in pods being rejected
even though they are running on the node (e.g., out of disk situation). This
change adds a condition to check whether the pod was seen before and categorize
such pods as updates. The change also removes freeze/unfreeze mechanism used to
work around such cases, since it is no longer needed and it stopped working
correctly ever since we switched to incremental updates.
Implement a flag that defines the frequency at which a node's out of
disk condition can change its status. Use this flag to suspend out of
disk status changes in the time period specified by the flag, after
the status is changed once.
Set the flag to 0 in e2e tests so that we can predictably test out of
disk node condition.
Also, use util.Clock interface for all time related functionality in
the kubelet. Calling time functions in unversioned package or time
package such as unversioned.Now() or time.Now() makes it really hard
to test such code. It also makes the tests flaky and sometimes
unnecessarily slow due to time.Sleep() calls used to simulate the
time elapsed. So use util.Clock interface instead which can be faked
in the tests.
Refactor Kubelet's server functionality into a server package. Most
notably, move pkg/kubelet/server.go into
pkg/kubelet/server/server.go. This will lead to better separation of
concerns and a more readable code hierarchy.
- Add volume.MetricsProvider function to Volume interface.
- Add volume.MetricsDu for providing metrics via executing "du".
- Add volulme.MetricsNil for unsupported Volumes.
Addresses a version skew issue where the last condition status is always
evaluated as the NodeReady status. As a workaround force the NodeReady
condition to be the last in the list of node conditions.
ref: https://github.com/kubernetes/kubernetes/issues/16961
This change introduces pod lifecycle event generator (PLEG), and adds a generic
PLEG. The generic PLEG relies on relisting to discover container events, and is
container-runtime-agnostic. Both docker and rkt are changed to use generic
PLEG.
- status.Manager always deals with the local (static) pod, but gets the
mirror pod when syncing
- This lets components like the probe workers ignore mirror pods
Now that kubelet checks sources seen correctly, there is no need to enforce the
initial order of pod updates and housekeeping. Use a ticker for housekeeping to
simplify the code.
Currently kubelet syncs all pods every 10s. This is not preferred because
* Some pods may have been sync'd recently.
* This may cause all the pods to be sync'd at once, causing undesirable
CPU spikes.
This PR replaces the global syncs with independent, periodic pod syncs. At the
end of syncing, each pod worker will enqueue itslef with a future timestamp (
current time + sync interval), when it will be due for another sync.
* If the pod worker encoutners an sync error, it may requeue with a different
timestamp to retry sooner.
* If a sync is triggered by the update channel (events or spec changes), the
pod worker would enqueue a new sync time.
This change is necessary for moving to long or no periodic sync period once pod
lifecycle event generator is completed. We will still rely on the mechanism to
requeue the pod on sync error.
This change also makes sure that if a sync does not succeed (either due to
real error or the per-container backoff mechanism), an error would be propagated
back to the pod worker, which is responsible for requeuing.
Define a new out of disk node condition and use it to report when node
goes out of disk.
Make a copy of loop range clause variable in node listers so that it
is available outside the for loop.
Also update/implement unit tests.
This commit builds on previous work and creates an independent
worker for every liveness probe. Liveness probes behave largely the same
as readiness probes, so much of the code is shared by introducing a
probeType paramater to distinguish the type when it matters. The
circular dependency between the runtime and the prober is broken by
exposing a shared liveness ResultsManager, owned by the
kubelet. Finally, an Updates channel is introduced to the ResultsManager
so the kubelet can react to unhealthy containers immediately.
