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the Node object annotation: ‘net.beta.kubernetes.io/proxy-mode’. If the
annotation is not specified, then ‘iptables’ mode is the default. If kube-proxy
is unable to start in iptables mode because system requirements are not met
(kernel or iptables versions are insufficient), the kube-proxy will fall-back
to userspace mode. Kube-proxy is much more performant and less
resource-intensive in ‘iptables’ mode.