Automatic merge from submit-queue
rkt: Add post-start hook support.
This adds a poll-and-timeout procedure after the pod is
started, to make sure the post-start hooks execute when the
container is actually running.
This is a temporal workaround for implementing post-hooks,
a long term solution is to use lifecycle event to trigger
those hooks, see https://github.com/kubernetes/kubernetes/issues/23084.
Also this fixes a bug of getting container ID for a non-running
container when running pre-stop hook.
cc @sjpotter @euank @kubernetes/sig-node
Automatic merge from submit-queue
Collect and expose runtime's image storage usage via Kubelet's /stats/summary endpoint
This information is useful to users since docker images are typically not stored on the root filesystem.
Kubelet will also consume this feature in the future to decide is evicting images will help with disk usage on the nodes.
cc @kubernetes/sig-node
This has been supplanted by a) the DockerJSON.CreatedAt field and b) the
ContainerStatus.CreatedAt, where the first is used for creating the
second.
The `.Created` field was only written to as far as I can see.
This adds a poll-and-timeout procedure after the pod is
started, to make sure the post-start hooks execute when the
container is actually running.
This is a temporal workaround for implementing post-hooks,
a long term solution is to use lifecycle event to trigger
those hooks, see https://github.com/kubernetes/kubernetes/issues/23084.
Also this fixes a bug of getting container ID for a non-running
container when running pre-stop hook.
This is implemented via touching a file on stop as a hook in the systemd
unit. The ctime of this file is then used to get the `finishedAt` time
in the future.
In addition, this changes the `startedAt` and `createdAt` to use the api
server's results rather than the annotations it previously used.
It's possible we might want to move this into the api in the future.
Fixes#23887
Automatic merge from submit-queue
rkt: Fix hostnetwork.
Mount hosts' /etc/hosts, /etc/resolv.conf, set host's hostname
when running the pod in the host's network.
Fix#24235
cc @kubernetes/sig-node
Mount hosts' /etc/hosts, /etc/resolv.conf, set host's hostname
when running the pod in the host's network.
Besides, do not set the DNS flags when running in host's network.
Previously, the service file's name is 'k8s_${POD_UID}.service',
which means we need to `systemctl daemon-reload` if the we replace
the content of the service file (e.g. pod is restarted).
However this makes the journal in the previous pod get disconnected.
This PR solves the issue by using the unique rkt uuid as the service
file's name. After the change, the service file's name will be:
'k8s_${rkt_uuid}.service'.
Add GeneratePodHostNameAndDomain() to RuntimeHelper to
get the hostname of the pod from kubelet.
Also update the logging flag to change the journal match from
_HOSTNAME to _MACHINE_ID.
Using json makes this robust to ENTRYPOINT/CMD that contains space.
Also removed 'RemainAfterExit' option, originally this option is
useful when we implement GetPods() by 'systemctl list-units'.
However since we are using rkt API service now, it's no longer needed.
This enables rkt runtime to setup versions during creation,
this fixes a kubelet nil pointer panic when kubelet tries to get the
rkt versions but it's not set.
Use an array to store the pod IDs and use that to build the pod array with consistent ordering,
instead of map ordering, which is random and causes test flakes.
