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Deprecate KubeletConfiguration flags
This is a follow-up to #53833 to deprecate the old flags in favor of the
config file.
```release-note
Flags that can be set via the Kubelet's --config file are now deprecated in favor of the file.
```
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Cap how long the kubelet waits when it has no client cert
If we go a certain amount of time without being able to create a client
cert and we have no current client cert from the store, exit. This
prevents a corrupted local copy of the cert from leaving the Kubelet in a
zombie state forever. Exiting allows a config loop outside the Kubelet
to clean up the file or the bootstrap client cert to get another client
cert.
Five minutes is a totally arbitary timeout, judged to give enough time for really slow static pods to boot.
@mikedanese
```release-note
Set an upper bound (5 minutes) on how long the Kubelet will wait before exiting when the client cert from disk is missing or invalid. This prevents the Kubelet from waiting forever without attempting to bootstrap a new client credentials.
```
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Add IPv6 to command options.
**What this PR does / why we need it**:
This PR adds IPv6 information to the descriptions for several command options.
[Related PR in kubernetes/website](https://github.com/kubernetes/website/pull/6498)
**Release note**:
```release-note
NONE
```
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Update bazelbuild/rules_go, kubernetes/repo-infra, and gazelle dependencies
**What this PR does / why we need it**: updates our bazelbuild/rules_go dependency in order to bump everything to go1.9.4. I'm separating this effort into two separate PRs, since updating rules_go requires a large cleanup, removing an attribute from most build rules.
**Release note**:
```release-note
NONE
```
Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
Deprecate kubelet flag for cadvisor port
**Which issue(s) this PR fixes**:
Issue: #56523
TL;DR the Kubelet's `stats/summary` API is the preferred way of monitoring the node. If you need additional metrics from cAdvisor, it can be run as a daemonset.
**Release note**:
```release-note
Deprecate the kubelet's cadvisor port
```
/assign @mtaufen @tallclair
cc @kubernetes/sig-node-pr-reviews
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Log the command line flags
**What this PR does / why we need it**:
With d7ddcca231, we lost the logging
of the flags. We should at least log what the command line flags
were used to start processes as those incredibly useful for trouble shooting.
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes #
**Special notes for your reviewer**:
/assign @deads2k
/assign @liggitt
**Release note**:
```release-note
NONE
```
With d7ddcca231, we lost the logging
of the flags. We should at least log what the command line flags
were used to start processes as those incredibly useful for trouble shooting.
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Secure Kubelet's componentconfig defaults while maintaining CLI compatibility
This updates the Kubelet's componentconfig defaults, while applying the legacy defaults to values from options.NewKubeletConfiguration(). This keeps defaults the same for the command line and improves the security of defaults when you load config from a file.
See: https://github.com/kubernetes/kubernetes/issues/53618
See: https://github.com/kubernetes/kubernetes/pull/53833#discussion_r166669931
Also moves EnableServer to KubeletFlags, per @tallclair's comments on #53833.
We should find way of generating documentation for config file defaults, so that people can easily look up what's different from flags.
```release-note
Action required: Default values differ between the Kubelet's componentconfig (config file) API and the Kubelet's command line. Be sure to review the default values when migrating to using a config file.
```
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Add 'none' option to EnforceNodeAllocatable
This lets us use omitempty on `EnforceNodeAllocatable`. We shouldn't treat
`nil` as different from `[]T{}`, because this can play havoc with
serializers (a-la #43203).
See: https://github.com/kubernetes/kubernetes/pull/53833#discussion_r166672137
```release-note
'none' can now be specified in KubeletConfiguration.EnforceNodeAllocatable (--enforce-node-allocatable) to explicitly disable enforcement.
```
Automatic merge from submit-queue (batch tested with PRs 57824, 58806, 59410, 59280). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
2nd try at using a vanity GCR name
The 2nd commit here is the changes relative to the reverted PR. Please focus review attention on that.
This is the 2nd attempt. The previous try (#57573) was reverted while we
figured out the regional mirrors (oops).
New plan: k8s.gcr.io is a read-only facade that auto-detects your source
region (us, eu, or asia for now) and pulls from the closest. To publish
an image, push k8s-staging.gcr.io and it will be synced to the regionals
automatically (similar to today). For now the staging is an alias to
gcr.io/google_containers (the legacy URL).
When we move off of google-owned projects (working on it), then we just
do a one-time sync, and change the google-internal config, and nobody
outside should notice.
We can, in parallel, change the auto-sync into a manual sync - send a PR
to "promote" something from staging, and a bot activates it. Nice and
visible, easy to keep track of.
xref https://github.com/kubernetes/release/issues/281
TL;DR:
* The new `staging-k8s.gcr.io` is where we push images. It is literally an alias to `gcr.io/google_containers` (the existing repo) and is hosted in the US.
* The contents of `staging-k8s.gcr.io` are automatically synced to `{asia,eu,us)-k8s.gcr.io`.
* The new `k8s.gcr.io` will be a read-only alias to whichever regional repo is closest to you.
* In the future, images will be promoted from `staging` to regional "prod" more explicitly and auditably.
```release-note
Use "k8s.gcr.io" for pulling container images rather than "gcr.io/google_containers". Images are already synced, so this should not impact anyone materially.
Documentation and tools should all convert to the new name. Users should take note of this in case they see this new name in the system.
```
This is the 2nd attempt. The previous was reverted while we figured out
the regional mirrors (oops).
New plan: k8s.gcr.io is a read-only facade that auto-detects your source
region (us, eu, or asia for now) and pulls from the closest. To publish
an image, push k8s-staging.gcr.io and it will be synced to the regionals
automatically (similar to today). For now the staging is an alias to
gcr.io/google_containers (the legacy URL).
When we move off of google-owned projects (working on it), then we just
do a one-time sync, and change the google-internal config, and nobody
outside should notice.
We can, in parallel, change the auto-sync into a manual sync - send a PR
to "promote" something from staging, and a bot activates it. Nice and
visible, easy to keep track of.
This adds context to all the relevant cloud provider interface signatures.
Callers of those APIs are currently satisfied using context.TODO().
There will be follow on PRs to push the context through the stack.
For an idea of the full scope of this change please look at PR #58532.
If we go a certain amount of time without being able to create a client
cert and we have no current client cert from the store, exit. This
prevents a corrupted local copy of the cert from leaving the Kubelet in a
zombie state forever. Exiting allows a config loop outside the Kubelet
to clean up the file or the bootstrap client cert to get another client
cert.
Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
Add call to addCredentialProviderFlags
**What this PR does / why we need it**:
Credential flags such as 'azure-container-registry-config' are still in use, call addCredentialProviderFlags to hook it up.
See:
https://github.com/kubernetes/kubernetes/pull/56995#issuecomment-361483382
**Which issue(s) this PR fixes**
Follow up of #56995
**Special notes for your reviewer**:
/assign @mtaufen @liggitt
**Release note**:
```release-note
NONE
```
They should both follow the convention of not being a pointer on the
internal type. This required adding a conversion function between
`int64` and `*int64`.
A side effect is this removes a warning in the generated code for the
apps API group.
This changes the Kubelet configuration flag precedence order so that
flags take precedence over config from files/ConfigMaps.
See #56171 for rationale.
Note: Feature gates accumulate with the following
precedence (greater number overrides lesser number):
1. file-based config
2. dynamic cofig
3. flag-based config
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Remove deprecated --require-kubeconfig flag, remove default --kubeconfig value
**What this PR does / why we need it**:
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes#41161
**Special notes for your reviewer**:
**Release note**:
```release-note
Remove deprecated --require-kubeconfig flag, remove default --kubeconfig value
```
Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
Removal of KubeletConfigFile feature gate: Step 1
This feature gate was redundant with the `--config` flag, which already
enables/disables loading Kubelet config from a file.
Since the gate guarded an alpha feature, removing it is not a violation
of our API guidelines.
Some stuff in `kubernetes/test-infra` currently sets the gate,
so removing will be a 3 step process:
1. This PR, which makes the gate a no-op.
2. Stop setting the gate in `kubernetes/test-infra`.
3. Completely remove the gate (this PR will get the release note).
```release-note
NONE
```
Automatic merge from submit-queue (batch tested with PRs 57973, 57990). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
Set pids limit at pod level
**What this PR does / why we need it**:
Add a new Alpha Feature to set a maximum number of pids per Pod.
This is to allow the use case where cluster administrators wish
to limit the pids consumed per pod (example when running a CI system).
By default, we do not set any maximum limit, If an administrator wants
to enable this, they should enable `SupportPodPidsLimit=true` in the
`--feature-gates=` parameter to kubelet and specify the limit using the
`--pod-max-pids` parameter.
The limit set is the total count of all processes running in all
containers in the pod.
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes#43783
**Special notes for your reviewer**:
**Release note**:
```release-note
New alpha feature to limit the number of processes running in a pod. Cluster administrators will be able to place limits by using the new kubelet command line parameter --pod-max-pids. Note that since this is a alpha feature they will need to enable the "SupportPodPidsLimit" feature.
```
This feature gate was redundant with the `--config` flag, which already
enables/disables loading Kubelet config from a file.
Since the gate guarded an alpha feature, removing it is not a violation
of our API guidelines.
Some stuff in `kubernetes/test-infra` currently sets the gate,
so removing will be a 3 step process:
1. This PR, which makes the gate a no-op.
2. Stop setting the gate in `kubernetes/test-infra`.
3. Completely remove the gate.
Automatic merge from submit-queue (batch tested with PRs 58547, 57228, 58528, 58499, 58618). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
Add TLS min version flag
Adds a flag for controlling the minimum TLS level allowed.
/assign liggitt
@kubernetes/sig-node-pr-reviews @k8s-mirror-api-machinery-pr-reviews
```release-note
--tls-min-version on kubelet and kube-apiserver allow for configuring minimum TLS versions
```
Add a new Alpha Feature to set a maximum number of pids per Pod.
This is to allow the use case where cluster administrators wish
to limit the pids consumed per pod (example when running a CI system).
By default, we do not set any maximum limit, If an administrator wants
to enable this, they should enable `SupportPodPidsLimit=true` in the
`--feature-gates=` parameter to kubelet and specify the limit using the
`--pod-max-pids` parameter.
The limit set is the total count of all processes running in all
containers in the pod.
Automatic merge from submit-queue (batch tested with PRs 57733, 57613, 57953). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
Explicit kubelet flags
The Kubelet was using the global flag set.
Libraries also often use the global flag set.
There are flags in the Kubelet's usage statement for which the Kubelet does not control registration.
This is bad, we must have full control of our command-line API.
This PR puts a stop to it.
I worked through the Kubelet's usage printout and tracked down the flags.
In the below list, flags with checkboxes are one of:
- explicitly **registered** in this PR
- thought about and outright **rejected**
- thought about and **registered-deprecated** for legacy reasons
For the others we need to figure out whether they should be **registered** or **rejected** or **registered-deprecated**.
### cadvisor:
grep commands, for reference:
```
# flag definitions in cadvisor
git grep -E "\"application_metrics_count_limit\"|\"boot_id_file\"|\"container_hints\"|\"containerd\"|\"docker\"|\"docker_env_metadata_whitelist\"|\"docker_only\"|\"docker_root\"|\"docker-tls\"|\"docker-tls-ca\"|\"docker-tls-cert\"|\"docker-tls-key\"|\"enable_load_reader\"|\"event_storage_age_limit\"|\"event_storage_event_limit\"|\"global_housekeeping_interval\"|\"housekeeping_interval\"|\"log_cadvisor_usage\"|\"machine_id_file\"|\"storage_driver_buffer_duration\"|\"storage_driver_db\"|\"storage_driver_host\"|\"storage_driver_password\"|\"storage_driver_secure\"|\"storage_driver_table\"|\"storage_driver_user\"" -- vendor/github.com/google/cadvisor
# flag invocations
git grep -E "\--application_metrics_count_limit|--boot_id_file|--container_hints|--containerd|--docker|--docker_env_metadata_whitelist|--docker_only|--docker_root|--docker_tls|--docker_tls_ca|--docker_tls_cert|--docker_tls_key|--enable_load_reader|--event_storage_age_limit|--event_storage_event_limit|--global_housekeeping_interval|--housekeeping_interval|--log_cadvisor_usage|--machine_id_file|--storage_driver_buffer_duration|--storage_driver_db|--storage_driver_host|--storage_driver_password|--storage_driver_secure|--storage_driver_table|--storage_driver_user" -- ':(exclude)pkg/generated/bindata.go' ':(exclude)Godeps' ':(exclude)CHANGELOG*' ':(exclude)vendor'
# normalized flag invocations
git grep -E "\--application-metrics-count-limit|--boot-id-file|--container-hints|--containerd|--docker|--docker-env-metadata-whitelist|--docker-only|--docker-root|--docker-tls|--docker-tls-ca|--docker-tls-cert|--docker-tls-key|--enable-load-reader|--event-storage-age-limit|--event-storage-event-limit|--global-housekeeping-interval|--housekeeping-interval|--log-cadvisor-usage|--machine-id-file|--storage-driver-buffer-duration|--storage-driver-db|--storage-driver-host|--storage-driver-password|--storage-driver-secure|--storage-driver-table|--storage-driver-user" -- ':(exclude)pkg/generated/bindata.go' ':(exclude)Godeps' ':(exclude)CHANGELOG*' ':(exclude)vendor'
# flag names
git grep -E "application_metrics_count_limit|boot_id_file|container_hints|containerd|docker|docker_env_metadata_whitelist|docker_only|docker_root|docker_tls|docker_tls_ca|docker_tls_cert|docker_tls_key|enable_load_reader|event_storage_age_limit|event_storage_event_limit|global_housekeeping_interval|housekeeping_interval|log_cadvisor_usage|machine_id_file|storage_driver_buffer_duration|storage_driver_db|storage_driver_host|storage_driver_password|storage_driver_secure|storage_driver_table|storage_driver_user" ':(exclude)pkg/generated/bindata.go' ':(exclude)Godeps' ':(exclude)CHANGELOG*' ':(exclude)vendor'
# normalized flag names
git grep -E "application-metrics-count-limit|boot-id-file|container-hints|containerd|docker|docker-env-metadata-whitelist|docker-only|docker-root|docker-tls|docker-tls-ca|docker-tls-cert|docker-tls-key|enable-load-reader|event-storage-age-limit|event-storage-event-limit|global-housekeeping-interval|housekeeping-interval|log-cadvisor-usage|machine-id-file|storage-driver-buffer-duration|storage-driver-db|storage-driver-host|storage-driver-password|storage-driver-secure|storage-driver-table|storage-driver-user" ':(exclude)pkg/generated/bindata.go' ':(exclude)Godeps' ':(exclude)CHANGELOG*' ':(exclude)vendor'
# normalized and underscore names combined
git grep -E "application_metrics_count_limit|boot_id_file|container_hints|containerd|docker|docker_env_metadata_whitelist|docker_only|docker_root|docker_tls|docker_tls_ca|docker_tls_cert|docker_tls_key|enable_load_reader|event_storage_age_limit|event_storage_event_limit|global_housekeeping_interval|housekeeping_interval|log_cadvisor_usage|machine_id_file|storage_driver_buffer_duration|storage_driver_db|storage_driver_host|storage_driver_password|storage_driver_secure|storage_driver_table|storage_driver_user|application-metrics-count-limit|boot-id-file|container-hints|containerd|docker-env-metadata-whitelist|docker-only|docker-root|docker-tls|docker-tls-ca|docker-tls-cert|docker-tls-key|enable-load-reader|event-storage-age-limit|event-storage-event-limit|global-housekeeping-interval|housekeeping-interval|log-cadvisor-usage|machine-id-file|storage-driver-buffer-duration|storage-driver-db|storage-driver-host|storage-driver-password|storage-driver-secure|storage-driver-table|storage-driver-user" ':(exclude)pkg/generated/bindata.go' ':(exclude)Godeps' ':(exclude)CHANGELOG*' ':(exclude)vendor'
```
- [x] --docker-root (**registered** - this is used in `cluster/saltbase/salt/kubelet/default`)
- [x] --housekeeping-interval (**registered** - e2e node tests rely on this (`test/e2e_node/resource_collector.go`))
- [x] --application-metrics-count-limit (**registered-deprecated** - temporarily register for legacy)
- [x] --boot-id-file (**registered-deprecated** - temporarily register for legacy)
- [x] --container-hints (**registered-deprecated** - temporarily register for legacy)
- [x] --containerd (**registered-deprecated** - temporarily register for legacy)
- [x] --docker (**registered-deprecated** - temporarily register for legacy)
- [x] --docker-env-metadata-whitelist (**registered-deprecated** - temporarily register for legacy)
- [x] --docker-only (**registered-deprecated** - temporarily register for legacy)
- [x] --docker-tls (**registered-deprecated** - temporarily register for legacy)
- [x] --docker-tls-ca (**registered-deprecated** - temporarily register for legacy)
- [x] --docker-tls-cert (**registered-deprecated** - temporarily register for legacy)
- [x] --docker-tls-key (**registered-deprecated** - temporarily register for legacy)
- [x] --enable-load-reader (**registered-deprecated** - temporarily register for legacy)
- [x] --event-storage-age-limit (**registered-deprecated** - the Kubelet overrides the default via the global flagset (`pkg/kubelet/cadvisor/cadvisor_linux.go`), but nothing else in core repo provides)
- [x] --event-storage-event-limit (**registered-deprecated** - the Kubelet overrides the default via the global flagset (`pkg/kubelet/cadvisor/cadvisor_linux.go`), but nothing else in core repo provides)
- [x] --global-housekeeping-interval (**registered-deprecated** - temporarily register for legacy)
- [x] --log-cadvisor-usage (**registered-deprecated** - temporarily register for legacy)
- [x] --machine-id-file (**registered-deprecated** - temporarily register for legacy)
- [x] --storage-driver-user (**registered-deprecated** - temporarily register for legacy)
- [x] --storage-driver-password (**registered-deprecated** - temporarily register for legacy)
- [x] --storage-driver-host (**registered-deprecated** - temporarily register for legacy)
- [x] --storage-driver-db (**registered-deprecated** - temporarily register for legacy)
- [x] --storage-driver-table (**registered-deprecated** - temporarily register for legacy)
- [x] --storage-driver-secure (**registered-deprecated** - temporarily register for legacy)
- [x] --storage-driver-buffer-duration (**registered-deprecated** - temporarily register for legacy)
### pkg/apiserver/util/logs:
- [x] --log-flush-frequency (**registered** - like the glog flags, this is probably useful)
### pkg/credentialprovider/azure/azure_credentials.go:
- [x] --azure-container-registry-config (**registered** - This isn't quite as straightforward as --google-json-key, because the file it points to isn't static. For now we will just register, and we will deprecate it when there is an alternative. See below comments.)
### pkg/credentialprovider/gcp/jwt.go:
- [x] --google-json-key (**registered-deprecated** - This is really old legacy stuff to allow kubelets to authenticate with gcr (see: d5e0054eb0). See @liggit's below comment for what should be used instead.)
### pkg/cloudprovider/providers/gce/gce_loadbalancer.go:
- [x] --cloud-provider-gce-lb-src-cidrs (**rejected** - Kubelet doesn't need to know about the cidrs that were opened in the firewall for the load balancer)
### glog:
I registered all of these, since this logging library is used pretty much everywhere in the Kubelet, and all of its toggles are probably useful.
- [x] --logtostderr (**registered**)
- [x] --alsologtostderr (**registered**)
- [x] -v, --v (**registered**)
- [x] --stderrthreshold (**registered**)
- [x] --vmodule (**registered**)
- [x] --log-backtrace-at (**registered**)
- [x] --log-dir (**registered**)
### verflag:
This is how you get the Kubelet's version, absolutely necessary to register this.
- [x] --version (**registered**)
```release-note
The Kubelet now explicitly registers all of its command-line flags with an internal flagset, which prevents flags from third party libraries from unintentionally leaking into the Kubelet's command-line API. Many unintentionally leaked flags are now marked deprecated, so that users have a chance to migrate away from them before they are removed. One previously leaked flag, --cloud-provider-gce-lb-src-cidrs, was entirely removed from the Kubelet's command-line API, because it is irrelevant to Kubelet operation.
```
Thanks to @liggitt for being surprised that we didn't already do this.
Thanks to @dashpole for realizing cadvisor flags were leaked after seeing #55863.
Thanks to @tallclair who recognized this problem a long time ago in #19432.
This explicitly registers Kubelet flags from libraries that were
registering flags globally, and stops parsing the global flag set.
In general, we should always be explicit about flags we register
and parse, so that we maintain control over our command-line API.
Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
Bump pause container used by kubelet and tests to 3.1
This updates the version of the pause container used by the kubelet and
various test utilities to 3.1.
**What this PR does / why we need it**: The pause container hasn't been rebuilt in quite a while and needs an update to reap zombies (#50865) and for schema2 manifest (#56253).
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes#50865, Fixes#56253
**Special notes for your reviewer**:
**Release note**:
```release-note
The kubelet uses a new release 3.1 of the pause container with the Docker runtime. This version will clean up orphaned zombie processes that it inherits.
```