Kube/proxy, in NodeCIDR local detector mode, uses the node.Spec.PodCIDRs
field to build the Services iptables rules.
The Node object depends on the kubelet, but if kube-proxy runs as a
static pods or as a standalone binary, it is not possible to guarantee
that the values obtained at bootsrap are valid, causing traffic outages.
Kube-proxy has to react on node changes to avoid this problems, it
simply restarts if detect that the node PodCIDRs have changed.
In case that the Node has been deleted, kube-proxy will only log an
error and keep working, since it may break graceful shutdowns of the
node.
