Add error details for setupIndieNetns

control/netns_utils.go

@@ -1,6 +1,7 @@
 package control
 
 import (
+	"fmt"
 	"net"
 	"os"
 	"path"
@@ -55,18 +56,18 @@ func setupIndieNetns() (err error) {
 
 	hostNetns, err := netns.Get()
 	if err != nil {
-		return
+		return fmt.Errorf("Failed to get host netns: %v", err)
 	}
 	defer netns.Set(hostNetns)
 
 	// ip netns a daens
 	DeleteNamedNetns("daens")
 	indieNetns, err = netns.NewNamed("daens")
 	if err != nil {
-		return
+		return fmt.Errorf("Failed to create netns: %v", err)
 	}
 	if err = netns.Set(hostNetns); err != nil {
-		return
+		return fmt.Errorf("Failed to switch to host netns: %v", err)
 	}
 	// ip l a dae0 type veth peer name dae0peer
 	DeleteLink("dae0")
@@ -76,62 +77,62 @@ func setupIndieNetns() (err error) {
 		},
 		PeerName: "dae0peer",
 	}); err != nil {
-		return
+		return fmt.Errorf("Failed to add veth pair: %v", err)
 	}
 	dae0, err := netlink.LinkByName("dae0")
 	if err != nil {
-		return
+		return fmt.Errorf("Failed to get link dae0: %v", err)
 	}
 	dae0peer, err := netlink.LinkByName("dae0peer")
 	if err != nil {
-		return
+		return fmt.Errorf("Failed to get link dae0peer: %v", err)
 	}
 	// ip l s dae0 up
 	if err = netlink.LinkSetUp(dae0); err != nil {
-		return
+		return fmt.Errorf("Failed to set link dae0 up: %v", err)
 	}
 	// sysctl net.ipv4.conf.{dae0,all}.rp_filter=0
 	if err = SetRpFilter("dae0", "0"); err != nil {
-		return
+		return fmt.Errorf("Failed to set rp_filter for dae0: %v", err)
 	}
 	if err = SetRpFilter("all", "0"); err != nil {
-		return
+		return fmt.Errorf("Failed to set rp_filter for all: %v", err)
 	}
 	// ip l s dae0peer netns daens
 	if err = netlink.LinkSetNsFd(dae0peer, int(indieNetns)); err != nil {
-		return
+		return fmt.Errorf("Failed to move dae0peer to daens: %v", err)
 	}
 	// ip net e daens
 	if err = netns.Set(indieNetns); err != nil {
-		return
+		return fmt.Errorf("Failed to switch to daens: %v", err)
 	}
 	// (ip net e daens) ip l s dae0peer up
 	if err = netlink.LinkSetUp(dae0peer); err != nil {
-		return
+		return fmt.Errorf("Failed to set link dae0peer up: %v", err)
 	}
 	// (ip net e daens) ip a a 169.254.0.1 dev dae0peer
 	ip, ipNet, err := net.ParseCIDR("169.254.0.1/24")
 	ipNet.IP = ip
 	if err != nil {
-		return
+		return fmt.Errorf("Failed to parse ip: %v", err)
 	}
 	if err = netlink.AddrAdd(dae0peer, &netlink.Addr{IPNet: ipNet}); err != nil {
-		return
+		return fmt.Errorf("Failed to add addr to dae0peer: %v", err)
 	}
 	// (ip net e daens) ip r a default dev dae0peer
 	if err = netlink.RouteAdd(&netlink.Route{
 		LinkIndex: dae0peer.Attrs().Index,
 		Dst:       &net.IPNet{IP: net.IPv4(0, 0, 0, 0), Mask: net.CIDRMask(0, 32)},
 		Gw:        nil,
 	}); err != nil {
-		return
+		return fmt.Errorf("Failed to add route to dae0peer: %v", err)
 	}
 	return
 }
 
 func DeleteNamedNetns(name string) error {
 	namedPath := path.Join("/run/netns", name)
-	unix.Unmount(namedPath, unix.MNT_DETACH)
+	unix.Unmount(namedPath, unix.MNT_DETACH|unix.MNT_FORCE)
 	return os.Remove(namedPath)
 }