If a pod is killed (no longer wanted) and then a subsequent create/
add/update event is seen in the pod worker, assume that a pod UID
was reused (as it could be in static pods) and have the next
SyncKnownPods after the pod terminates remove the worker history so
that the config loop can restart the static pod, as well as return
to the caller the fact that this termination was not final.
The housekeeping loop then reconciles the desired state of the Kubelet
(pods in pod manager that are not in a terminal state, i.e. admitted
pods) with the pod worker by resubmitting those pods. This adds a
small amount of latency (2s) when a pod UID is reused and the pod
is terminated and restarted.
A pod that has been rejected by admission will have status manager
set the phase to Failed locally, which make take some time to
propagate to the apiserver. The rejected pod will be included in
admission until the apiserver propagates the change back, which
was an unintended regression when checking pod worker state as
authoritative.
A pod that is terminal in the API may still be consuming resources
on the system, so it should still be included in admission.
The configuration is deprecated and targets removal for v1.23. Tests
cases have been changed as well.
Signed-off-by: Sascha Grunert <sgrunert@redhat.com>
* Change uses of whitelist to allowlist in kubelet sysctl
* Rename whitelist files to allowlist in Kubelet sysctl
* Further renames of whitelist to allowlist in Kubelet
* Rename podsecuritypolicy uses of whitelist to allowlist
* Update pkg/kubelet/kubelet.go
Co-authored-by: Danielle <dani@builds.terrible.systems>
Co-authored-by: Danielle <dani@builds.terrible.systems>
Prevent Kubelet from incorrectly interpreting "not yet started" pods as "ready to terminate pods" by unifying responsibility for pod lifecycle into pod worker
oomwatcher.NewWatcher returns "open /dev/kmsg: operation not permitted" error,
when running with sysctl value `kernel.dmesg_restrict=1`.
The error is negligible for KubeletInUserNamespace.
Signed-off-by: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>
A number of race conditions exist when pods are terminated early in
their lifecycle because components in the kubelet need to know "no
running containers" or "containers can't be started from now on" but
were relying on outdated state.
Only the pod worker knows whether containers are being started for
a given pod, which is required to know when a pod is "terminated"
(no running containers, none coming). Move that responsibility and
podKiller function into the pod workers, and have everything that
was killing the pod go into the UpdatePod loop. Split syncPod into
three phases - setup, terminate containers, and cleanup pod - and
have transitions between those methods be visible to other
components. After this change, to kill a pod you tell the pod worker
to UpdatePod({UpdateType: SyncPodKill, Pod: pod}).
Several places in the kubelet were incorrect about whether they
were handling terminating (should stop running, might have
containers) or terminated (no running containers) pods. The pod worker
exposes methods that allow other loops to know when to set up or tear
down resources based on the state of the pod - these methods remove
the possibility of race conditions by ensuring a single component is
responsible for knowing each pod's allowed state and other components
simply delegate to checking whether they are in the window by UID.
Removing containers now no longer blocks final pod deletion in the
API server and are handled as background cleanup. Node shutdown
no longer marks pods as failed as they can be restarted in the
next step.
See https://docs.google.com/document/d/1Pic5TPntdJnYfIpBeZndDelM-AbS4FN9H2GTLFhoJ04/edit# for details
This adds the gate `SeccompDefault` as new alpha feature. Seccomp path
and field fallbacks are now passed to the helper functions, whereas unit
tests covering those code paths have been added as well.
Beside enabling the feature gate, the feature has to be enabled by the
`SeccompDefault` kubelet configuration or its corresponding
`--seccomp-default` CLI flag.
Signed-off-by: Sascha Grunert <sgrunert@redhat.com>
Apply suggestions from code review
Co-authored-by: Paulo Gomes <pjbgf@linux.com>
Signed-off-by: Sascha Grunert <sgrunert@redhat.com>
FeatureGate acts as a secondary switch to disable cloud-controller loops
in KCM, Kubelet and KAPI.
Provide comprehensive logging information to users, so they will be
guided in adoption of out-of-tree cloud provider implementation.
GetNode() is called in a lot of places including a hot loop in
fastStatusUpdateOnce. Having a poll in it is delaying
the kubelet /readyz status=200 report.
If a client is available attempt to wait for the sync to happen,
before starting the list watch for pods at the apiserver.
