docs(quickstart): add Linux inotify prerequisite note#134
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The default fs.inotify.max_user_instances=128 is exhausted when running multiple Kind clusters, causing containerd inside the ControlPlane cluster to fail. This delays bootstrap significantly and triggers the exponential backoff bug described in cluster-provider-kind#163. Validated by reproducing the failure at 128 and confirming clean runs at 512. Signed-off-by: Michael Sprauer <Michael.Sprauer@sap.com>
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Summary
fs.inotify.max_user_instancesbefore running the tutorial.sysctlcommands to apply the fix immediately, plus the persistence step (/etc/sysctl.d/99-kind.conf).Background
The default Linux inotify limit (
max_user_instances=128) is exhausted when running multiple Kind clusters simultaneously. When it is hit,containerdinside the ControlPlane Kind cluster fails to initialize, which delays the API server bootstrap significantly. This in turn triggers the exponential backoff bug described in cluster-provider-kind#163: theAccessRequestcontroller builds up a large backoff interval before the API server becomes reachable, leaving theAccessRequeststuck inPendingfor several minutes after the cluster is already healthy.Test plan
max_user_instances=128:AccessRequeststaysPending,clustercontroller logscould not find a log line matching "Reached target Multi-User System", backoff grows to 328s → 600s capmax_user_instances=512: full quickstart completes in under 7 minutes,AccessRequestgranted on first attempt with zero errors