c.FuzzNoCustom(obj)

	// Pinning values for fields that get defaults if fuzz value is empty string or nil (thus making the round trip test fail)
	obj.IgnorePreflightErrors = nil
	obj.ImagePullSerial = ptr.To(true)
}

func fuzzClusterConfiguration(obj *kubeadm.ClusterConfiguration, c fuzz.Continue) {
	c.FuzzNoCustom(obj)

	oldPools, allPools = allPools, nil
}

var (
	allPoolsMu Mutex

	// allPools is the set of pools that have non-empty primary
	// caches. Protected by either 1) allPoolsMu and pinning or 2)
	// STW.
	allPools []*Pool

	// oldPools is the set of pools that may have non-empty victim
	// caches. Protected by STW.
	oldPools []*Pool
)

func init() {

	return r, nil
}

func lookupPTR(name string) (ptr []string, err error) {
	var r string
	if r, err = ping(name); err != nil {
		return
	}
	ptr = make([]string, 0, 10)
	rx := regexp.MustCompile(`(?m)^Pinging\s+([a-zA-Z0-9.\-]+)\s+\[.*$`)
	for _, ans := range rx.FindAllStringSubmatch(r, -1) {
		ptr = append(ptr, absDomainName(ans[1]))
	}
	return
}

func localIP() (ip IP, err error) {