- Name the function GetConfigMapWithShortRetry to be
easier to understand that the function is with a very short timeout.
Add note that this function should be used in cases there is a
fallback to local config.
- Apply custom hardcoded interval of 50ms and timeout of 350ms to it.
Previously the fucntion used exp backoff with 5 steps up to ~340ms.
Switch to PollUntilContextTimeout() everywhere to allow
usage of the exposed timeouts in the kubeadm API. Exponential backoff
options are more difficult to expose in this regard and a bit too
detailed for the common user - i.e. have "steps", "factor" and so on.
Replace the usage of the deprecated wait.Poll() and
wait.PollImmediate() functions with wait.PollUntilContextTimeout().
Since we don't have piping of context around kubeadm,
use context.Background() everywhere.
Some wait.Poll() functions were converted to "immediate" as there
is no point for them to not be. This is done for consistency.
Replace the only instance of wait.JitterUntil with
wait.PollUntilContextTimeout. JitterUntil is not deprecated
but this is also done for consistency.
If the user deletes the /var/lib/kubelet manually, "reset" will throw
an error that the dir is missing. Instead of handling this error,
print it as a warning and skip unmount of directories inside it.
This allows "reset" to continue to be reentrant and can be called
even even if "init/join" are not called yet and some of the
k8s directories on a node do not exist.
Continue to error on individual unmount errors.
Remove the function absoluteKubeletRunDirectory() and
call filepath.EvalSymlinks() directly.
Currently, timeouts are only accessible if a kubeadm runtime.Object{}
like InitConfiguration is passed around.
Any time a config is loaded or defaulted, store the Timeouts
structure in a thread-safe way in the main kubeadm API package
with SetActiveTimeouts(). Optionally, a deep-copy can be
performed before calling SetActiveTimeouts(). Make this struct
accessible with GetActiveTimeouts(). Ensure these functions
are thread safe.
On init() make sure the struct is defaulted, so that unit
tests can work with these values.
When upconverting from v1beta3 to v1beta4, it appears there is no
easy way to migrate some of the timeout values such as:
ClusterConfiguration.APIServer.TimeoutForControlPlane
to a new location:
InitConfiguration.Timeouts.<some-timeout-field>
Yes, the internal InitConfiguratio does embed a ClusterConfiguration,
but during conversion the ClusterConfiguration is converted from an
empty source.
K8s' API machinery has ways to register custom conversion functions,
such as v1beta3.ClusterConfiguration -> internal.InitConfiguration,
but these must be triggered explicitly with a decoder.
The overall migration of fields seems very awkward.
There might be hacks around that, such as storing intermediate state,
while trying to make the fuzzer rountrip happy, but instead
mutation functions can be implemented for the internal types when
calling kubeadm's migrate code. This seems much cleaner.
The struct is included in InitConfiguration, JoinConfiguration
and ResetConfiguration.
Add conversion and update defaulters and fuzzers.
Include a timeoututils.go that contains a function
to default the internal Timeouts struct.
Add new a v1beta4.ResetConfiguration.UnmountFlags field that
can be used to pass in Linux unmount2() flags such as MNT_FORCE.
Default value continues to be 0 - i.e. no flags.
Instead of warnings when syscall.Unmount() causes errors,
store all the errors in an aggregate. Abort the reset operation if
at least one unmount error was encountered.
The function TryRunCommand() uses an exponential backoff,
which is good, but it's inconsistent and only used in a couple
of places.
Remove its usage in the token.go#UpdateOrCreateTokens()
and switch to using the standard function used in other places -
PollUntilContextTimeout().
Remove wait.go#TryRunCommand(), as there are no other usages.
The function wait.go#WaitForKubeletAndFunc() has been used in
a number of places in kubeadm. It starts a go routine to wait for
the kubelet /healthz and in parallel starts another go routine
to wait for an custom function.
This logic is problematic. If kubeadm is waiting for the kubelet
in parallel with something that requires the kubelet, the right
solution would be to first wait for the kubelet in serial and only
then proceed with the other action. The parallelism here particularly
during "init" required a unwanted "initial timeout" of 40s, before
the kubelet waiting even starts. In most cases, this makes the kubelet
waiter to not even start, while the main point of waiting becomes
the "other action".
- Remove the function WaitForKubeletAndFunc() from the Waiter interface.
- Rename the function WaitForHealthyKubelet() to just WaitForKubelet()
to be consistent with the naming WaitForAPI().
- Update WaitForKubelet() to not use TryRunCommand() and instead
use PollUntilContextTimeout().
- Remove the "initial timeout" of 40s in WaitForKubelet().
- Make both WaitForKubelet() and WaitForAPI() use similar error
handling and output.
- Update all usage of WaitForKubelet() to be a serial call before
any other action, such as another wait* call.
- Make the default wait timeout for the kubelet
/healthz to be 1 minute (kubeadmconstants.DefaultKubeletTimeout).
- Apply updates to all implementations of the Waiter interface.
Explictly show the help msg that `kubeadm upgrade plan` can only run
on the node where "admin.conf" exists, normally, this is the control
plane node.
Signed-off-by: Dave Chen <dave.chen@arm.com>
