All Kubernetes commands should show flags with hyphens in their help text even
when the flag originally was defined with underscore. Converting a command to
this style is not breaking its command line API because the old-style parameter
with underscore is accepted as alias.
The easiest solution to achieve this is to set normalization shortly before
running the command in the new central cli.Run or the few places where that
function isn't used yet.
There may be some texts which depends on normalization at flag definition time,
like the --logging-format usage warning. Those get generated assuming that
hyphens will be used.
It wasn't documented that InitLogs already uses the log flush frequency, so
some commands have called it before parsing (for example, kubectl in the
original code for logs.go). The flag never had an effect in such commands.
Fixing this turned into a major refactoring of how commands set up flags and
run their Cobra command:
- component-base/logs: implicitely registering flags during package init is an
anti-pattern that makes it impossible to use the package in commands which
want full control over their command line. Logging flags must be added
explicitly now, something that the new cli.Run does automatically.
- component-base/logs: AddFlags would have crashed in kubectl-convert if it
had been called because it relied on the global pflag.CommandLine. This
has been fixed and kubectl-convert now has the same --log-flush-frequency
flag as other commands.
- component-base/logs/testinit: an exception are tests where flag.CommandLine has
to be used. This new package can be imported to add flags to that
once per test program.
- Normalization of the klog command line flags was inconsistent. Some commands
unintentionally didn't normalize to the recommended format with hyphens. This
gets fixed for sample programs, but not for production programs because
it would be a breaking change.
This refactoring has the following user-visible effects:
- The validation error for `go run ./cmd/kube-apiserver --logging-format=json
--add-dir-header` now references `add-dir-header` instead of `add_dir_header`.
- `staging/src/k8s.io/cloud-provider/sample` uses flags with hyphen instead of
underscore.
- `--log-flush-frequency` is not listed anymore in the --logging-format flag's
`non-default formats don't honor these flags` usage text because it will also
work for non-default formats once it is needed.
- `cmd/kubelet`: the description of `--logging-format` uses hyphens instead of
underscores for the flags, which now matches what the command is using.
- `staging/src/k8s.io/component-base/logs/example/cmd`: added logging flags.
- `apiextensions-apiserver` no longer prints a useless stack trace for `main`
when command line parsing raises an error.
Because the proxy.Provider interface included
proxyconfig.EndpointsHandler, all the backends needed to
implement its methods. But iptables, ipvs, and winkernel implemented
them as no-ops, and metaproxier had an implementation that wouldn't
actually work (because it couldn't handle Services with no active
Endpoints).
Since Endpoints processing in kube-proxy is deprecated (and can't be
re-enabled unless you're using a backend that doesn't support
EndpointSlice), remove proxyconfig.EndpointsHandler from the
definition of proxy.Provider and drop all the useless implementations.
With this commit kube-proxy accepts current system values (retrieved by sysctl) which are higher than the internally known and expected values.
The code change was mistakenly created as PR in the k3s project (see https://github.com/k3s-io/k3s/pull/3505).
A real life use case is described in Rancher issue https://github.com/rancher/rancher/issues/33360.
When Kubernetes runs on a Node which itself is a container (e.g. LXC), and the value is changed on the (LXC) host, kube-proxy then fails at the next start as it does not recognize the current value and attempts to overwrite the current value with the previously known one. This result in:
```
I0624 07:38:23.053960 54 conntrack.go:103] Set sysctl 'net/netfilter/nf_conntrack_max' to 524288
F0624 07:38:23.053999 54 server.go:495] open /proc/sys/net/netfilter/nf_conntrack_max: permission denied
```
However a sysctl overwrite only makes sense if the current value is lower than the previously known and expected value. If the value was increased on the host, that shouldn't really bother kube-proxy and just go on with it.
Signed-off-by: Claudio Kuenzler ck@claudiokuenzler.com
We were detecting the IP family that kube-proxy should use
based on the bind address, however, this is not valid when
using an unspecified address, because on those cases
kube-proxy adopts the IP family of the address reported
in the Node API object.
The IP family will be determined by the nodeIP used by the proxier
The order of precedence is:
1. config.bindAddress if bindAddress is not 0.0.0.0 or ::
2. the primary IP from the Node object, if set
3. if no IP is found it defaults to 127.0.0.1 and IPv4
Signed-off-by: Antonio Ojea <antonio.ojea.garcia@gmail.com>
In case a malformed flag is passed to k8s components
such as "–foo", where "–" is not an ASCII dash character,
the components currently silently ignore the flag
and treat it as a positional argument.
Make k8s components/commands exit with an error if a positional argument
that is not empty is found. Include a custom error message for all
components except kubeadm, as cobra.NoArgs is used in a lot of
places already (can be fixed in a followup).
The kubelet already handles this properly - e.g.:
'unknown command: "–foo"'
This change affects:
- cloud-controller-manager
- kube-apiserver
- kube-controller-manager
- kube-proxy
- kubeadm {alpha|config|token|version}
- kubemark
Signed-off-by: Monis Khan <mok@vmware.com>
Signed-off-by: Lubomir I. Ivanov <lubomirivanov@vmware.com>
This builds on previous work but only sets the sysctlConnReuse value
if the kernel is known to be above 4.19. To avoid calling GetKernelVersion
twice, I store the value from the CanUseIPVS method and then check the version
constraint at time of expected sysctl call.
Signed-off-by: Christopher M. Luciano <cmluciano@us.ibm.com>
This creates a new EndpointSliceProxying feature gate to cover EndpointSlice
consumption (kube-proxy) and allow the existing EndpointSlice feature gate to
focus on EndpointSlice production only. Along with that addition, this enables
the EndpointSlice feature gate by default, now only affecting the controller.
The rationale here is that it's really difficult to guarantee all EndpointSlices
are created in a cluster upgrade process before kube-proxy attempts to consume
them. Although masters are generally upgraded before nodes, and in most cases,
the controller would have enough time to create EndpointSlices before a new node
with kube-proxy spun up, there are plenty of edge cases where that might not be
the case. The primary limitation on EndpointSlice creation is the API rate limit
of 20QPS. In clusters with a lot of endpoints and/or with a lot of other API
requests, it could be difficult to create all the EndpointSlices before a new
node with kube-proxy targeting EndpointSlices spun up.
Separating this into 2 feature gates allows for a more gradual rollout with the
EndpointSlice controller being enabled by default in 1.18, and EndpointSlices
for kube-proxy being enabled by default in the next release.
This patch removes pkg/util/mount completely, and replaces it with the
mount package now located at k8s.io/utils/mount. The code found at
k8s.io/utils/mount was moved there from pkg/util/mount, so the code is
identical, just no longer in-tree to k/k.
Removed unneeded comments
Matched style from other PR's
Only print error when lenient decoding is successful
Update Bazel for BUILD
Comment out existing strict decoder tests
Added tests for leniant path
Added comments to explain test additions
Cleanup TODO's and tests
Add explicit newline for appended config
