Init ipvsInterface only when ipvs modules are present

cmd/kube-proxy/app/server_others.go

@@ -92,9 +92,11 @@ func newProxyServer(
 
 	dbus = utildbus.New()
 	iptInterface = utiliptables.New(execer, dbus, protocol)
-	ipvsInterface = utilipvs.New(execer)
 	kernelHandler = ipvs.NewLinuxKernelHandler()
 	ipsetInterface = utilipset.New(execer)
+	if canUse, _ := ipvs.CanUseIPVSProxier(kernelHandler, ipsetInterface); canUse {
+		ipvsInterface = utilipvs.New(execer)
+	}
 
 	// We omit creation of pretty much everything if we run in cleanup mode
 	if cleanupAndExit {

pkg/proxy/ipvs/proxier.go

@@ -547,6 +547,9 @@ func cleanupIptablesLeftovers(ipt utiliptables.Interface) (encounteredError bool
 
 // CleanupLeftovers clean up all ipvs and iptables rules created by ipvs Proxier.
 func CleanupLeftovers(ipvs utilipvs.Interface, ipt utiliptables.Interface, ipset utilipset.Interface, cleanupIPVS bool) (encounteredError bool) {
+	if canUse, _ := CanUseIPVSProxier(NewLinuxKernelHandler(), ipset); !canUse {
+		return false
+	}
 	if cleanupIPVS {
 		// Return immediately when ipvs interface is nil - Probably initialization failed in somewhere.
 		if ipvs == nil {