As of now, we allow PDBs to be applied to pods via
selectors, so there can be unmanaged pods(pods that
don't have backing controllers) but still have PDBs associated.
Such pods are to be logged instead of immediately throwing
a sync error. This ensures disruption controller is
not frequently updating the status subresource and thus
preventing excessive and expensive writes to etcd.
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>
Errors during setting the following sysctl values are ignored:
- vm.overcommit_memory
- vm.panic_on_oom
- kernel.panic
- kernel.panic_on_oops
- kernel.keys.root_maxkeys
- kernel.keys.root_maxbytes
Signed-off-by: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>
Enables support for running kubelet in a user namespace.
The user namespace has to be created before running kubelet.
All the node components such as CRI need to be running in the same user namespace.
See kubernetes/enhancements PR 1371 (merged) and issue 2033.
Signed-off-by: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>
Modify the behavior of the AnyVolumeDataSource alpha feature gate to enable
a new field, DataSourceRef, rather than modifying the behavior of the
existing DataSource field. This allows addition Volume Populators in a way
that doesn't risk breaking backwards compatibility, although it will
result in eventually deprecating the DataSource field.
runtimes may return an arbitrary number of Pod IPs, however, kubernetes
only takes into consideration the first one of each IP family.
The order of the IPs are the one defined by the Kubelet:
- default prefer IPv4
- if NodeIPs are defined, matching the first nodeIP family
PodIP is always the first IP of PodIPs.
The downward API must expose the same IPs and in the same order than
the pod.Status API object.
With the client-go credential plugin functionality going GA in 1.22,
it is now time to deprecate these legacy integrations.
Signed-off-by: Monis Khan <mok@vmware.com>
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were relying on outdated state.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
