Delete the interface on endpoint delete in overlay

- Attempt the veth delete only after both ends
  are moved into the default network namespace.
  Which is after both driver.Leave() and
  sandbox.clearNetworkResources() are called.

Signed-off-by: Alessandro Boch <aboch@docker.com>

libnetwork/drivers/overlay/joinleave.go

@@ -49,33 +49,33 @@ func (d *driver) Join(nid, eid string, sboxKey string, jinfo driverapi.JoinInfo,
 
 	sbox := n.sandbox()
 
-	name1, name2, err := createVethPair()
+	overlayIfName, containerIfName, err := createVethPair()
 	if err != nil {
 		return err
 	}
 
-	ep.ifName = name2
+	ep.ifName = overlayIfName
 
 	// Set the container interface and its peer MTU to 1450 to allow
 	// for 50 bytes vxlan encap (inner eth header(14) + outer IP(20) +
 	// outer UDP(8) + vxlan header(8))
-	veth, err := netlink.LinkByName(name1)
+	veth, err := netlink.LinkByName(overlayIfName)
 	if err != nil {
-		return fmt.Errorf("cound not find link by name %s: %v", name1, err)
+		return fmt.Errorf("cound not find link by name %s: %v", overlayIfName, err)
 	}
 	err = netlink.LinkSetMTU(veth, vxlanVethMTU)
 	if err != nil {
 		return err
 	}
 
-	if err := sbox.AddInterface(name1, "veth",
+	if err := sbox.AddInterface(overlayIfName, "veth",
 		sbox.InterfaceOptions().Master(s.brName)); err != nil {
 		return fmt.Errorf("could not add veth pair inside the network sandbox: %v", err)
 	}
 
-	veth, err = netlink.LinkByName(name2)
+	veth, err = netlink.LinkByName(containerIfName)
 	if err != nil {
-		return fmt.Errorf("could not find link by name %s: %v", name2, err)
+		return fmt.Errorf("could not find link by name %s: %v", containerIfName, err)
 	}
 	err = netlink.LinkSetMTU(veth, vxlanVethMTU)
 	if err != nil {
@@ -96,7 +96,7 @@ func (d *driver) Join(nid, eid string, sboxKey string, jinfo driverapi.JoinInfo,
 	}
 
 	if iNames := jinfo.InterfaceName(); iNames != nil {
-		err = iNames.SetNames(name2, "eth")
+		err = iNames.SetNames(containerIfName, "eth")
 		if err != nil {
 			return err
 		}
@@ -136,14 +136,5 @@ func (d *driver) Leave(nid, eid string) error {
 
 	n.leaveSandbox()
 
-	link, err := netlink.LinkByName(ep.ifName)
-	if err != nil {
-		log.Warnf("Failed to retrieve interface link for interface removal on endpoint leave: %v", err)
-		return nil
-	}
-	if err := netlink.LinkDel(link); err != nil {
-		log.Warnf("Failed to delete interface link on endpoint leave: %v", err)
-	}
-
 	return nil
 }

libnetwork/drivers/overlay/ov_endpoint.go

@@ -4,8 +4,10 @@ import (
 	"fmt"
 	"net"
 
+	log "github.com/Sirupsen/logrus"
 	"github.com/docker/libnetwork/driverapi"
 	"github.com/docker/libnetwork/netutils"
+	"github.com/vishvananda/netlink"
 )
 
 type endpointTable map[string]*endpoint
@@ -97,6 +99,20 @@ func (d *driver) DeleteEndpoint(nid, eid string) error {
 	}
 
 	n.deleteEndpoint(eid)
+
+	if ep.ifName == "" {
+		return nil
+	}
+
+	link, err := netlink.LinkByName(ep.ifName)
+	if err != nil {
+		log.Debugf("Failed to retrieve interface (%s)'s link on endpoint (%s) delete: %v", ep.ifName, ep.id, err)
+		return nil
+	}
+	if err := netlink.LinkDel(link); err != nil {
+		log.Debugf("Failed to delete interface (%s)'s link on endpoint (%s) delete: %v", ep.ifName, ep.id, err)
+	}
+
 	return nil
 }
 

libnetwork/drivers/overlay/ov_network.go

@@ -160,7 +160,9 @@ func (n *network) destroySandbox() {
 	sbox := n.sandbox()
 	if sbox != nil {
 		for _, iface := range sbox.Info().Interfaces() {
-			iface.Remove()
+			if err := iface.Remove(); err != nil {
+				logrus.Debugf("Remove interface %s failed: %v", iface.SrcName(), err)
+			}
 		}
 
 		for _, s := range n.subnets {

libnetwork/osl/interface_linux.go

@@ -8,6 +8,7 @@ import (
 	"sync"
 	"syscall"
 
+	log "github.com/Sirupsen/logrus"
 	"github.com/docker/libnetwork/types"
 	"github.com/vishvananda/netlink"
 )
@@ -127,7 +128,7 @@ func (i *nwIface) Remove() error {
 
 		err = netlink.LinkSetName(iface, i.SrcName())
 		if err != nil {
-			fmt.Println("LinkSetName failed: ", err)
+			log.Debugf("LinkSetName failed for interface %s: %v", i.SrcName(), err)
 			return err
 		}
 
@@ -139,7 +140,7 @@ func (i *nwIface) Remove() error {
 		} else if !isDefault {
 			// Move the network interface to caller namespace.
 			if err := netlink.LinkSetNsFd(iface, callerFD); err != nil {
-				fmt.Println("LinkSetNsPid failed: ", err)
+				log.Debugf("LinkSetNsPid failed for interface %s: %v", i.SrcName(), err)
 				return err
 			}
 		}

libnetwork/sandbox.go

@@ -589,7 +589,7 @@ func releaseOSSboxResources(osSbox osl.Sandbox, ep *endpoint) {
 		// Only remove the interfaces owned by this endpoint from the sandbox.
 		if ep.hasInterface(i.SrcName()) {
 			if err := i.Remove(); err != nil {
-				log.Debugf("Remove interface failed: %v", err)
+				log.Debugf("Remove interface %s failed: %v", i.SrcName(), err)
 			}
 		}
 	}