func configureIface(ifname string, ipn ip.IP4Net, mtu int) error { iface, err := netlink.LinkByName(ifname) if err != nil { return fmt.Errorf("failed to lookup interface %v", ifname) } err = netlink.AddrAdd(iface, &netlink.Addr{ipn.ToIPNet(), ""}) if err != nil { return fmt.Errorf("failed to add IP address %v to %v: %v", ipn.String(), ifname, err) } err = netlink.LinkSetMTU(iface, mtu) if err != nil { return fmt.Errorf("failed to set MTU for %v: %v", ifname, err) } err = netlink.LinkSetUp(iface) if err != nil { return fmt.Errorf("failed to set interface %v to UP state: %v", ifname, err) } // explicitly add a route since there might be a route for a subnet already // installed by Docker and then it won't get auto added err = netlink.RouteAdd(&netlink.Route{ LinkIndex: iface.Attrs().Index, Scope: netlink.SCOPE_UNIVERSE, Dst: ipn.Network().ToIPNet(), }) if err != nil && err != syscall.EEXIST { return fmt.Errorf("Failed to add route (%v -> %v): %v", ipn.Network().String(), ifname, err) } return nil }
func ensureLink(vxlan *netlink.Vxlan) (*netlink.Vxlan, error) { err := netlink.LinkAdd(vxlan) if err == syscall.EEXIST { // it's ok if the device already exists as long as config is similar existing, err := netlink.LinkByName(vxlan.Name) if err != nil { return nil, err } incompat := vxlanLinksIncompat(vxlan, existing) if incompat == "" { return existing.(*netlink.Vxlan), nil } // delete existing log.Warningf("%q already exists with incompatable configuration: %v; recreating device", vxlan.Name, incompat) if err = netlink.LinkDel(existing); err != nil { return nil, fmt.Errorf("failed to delete interface: %v", err) } // create new if err = netlink.LinkAdd(vxlan); err != nil { return nil, fmt.Errorf("failed to create vxlan interface: %v", err) } } else if err != nil { return nil, err } ifindex := vxlan.Index link, err := netlink.LinkByIndex(vxlan.Index) if err != nil { return nil, fmt.Errorf("can't locate created vxlan device with index %v", ifindex) } var ok bool if vxlan, ok = link.(*netlink.Vxlan); !ok { return nil, fmt.Errorf("created vxlan device with index %v is not vxlan", ifindex) } return vxlan, nil }