func createSlaveInterfaces(netCfg *NetworkConfig) {
links, err := netlink.LinkList()
if err != nil {
log.Errorf("Failed to list links: %v", err)
return
}
for _, link := range links {
match, ok := findMatch(link, netCfg)
if !ok {
continue
}
vlanDefs, err := ParseVlanDefinitions(match.Vlans)
if err != nil {
log.Errorf("Failed to create vlans on device %s: %v", link.Attrs().Name, err)
continue
}
for _, vlanDef := range vlanDefs {
if _, err = NewVlan(link, vlanDef.Name, vlanDef.Id); err != nil {
log.Errorf("Failed to create vlans on device %s, id %d: %v", link.Attrs().Name, vlanDef.Id, err)
}
}
}
}
// Address specific
func handleAddr(update netlink.AddrUpdate, callback func(supervisor.NetlinkUpdate)) {
if update.NewAddr {
fmt.Printf("[Add a address]")
} else {
fmt.Printf("[Delete a address]")
}
if update.LinkAddress.IP.To4() != nil {
fmt.Printf("[IPv4]\t%+v\n", update)
} else {
// We would not like to handle IPv6 at present.
fmt.Printf("[IPv6]\t%+v\n", update)
return
}
netlinkUpdate := supervisor.NetlinkUpdate{}
netlinkUpdate.Addr = update
netlinkUpdate.UpdateType = supervisor.UpdateTypeAddr
links, err := netlink.LinkList()
if err != nil {
glog.Error(err)
}
for _, link := range links {
if link.Attrs().Index == update.LinkIndex && link.Type() == "veth" {
netlinkUpdate.Veth = link.(*netlink.Veth)
break
}
}
callback(netlinkUpdate)
}
func resourceLXCBridgeDelete(d *schema.ResourceData, meta interface{}) error {
bridgeIndex, err := strconv.Atoi(d.Id())
if err != nil {
return fmt.Errorf("Internal error reading resource ID: %v", err)
}
bridge, err := netlink.LinkByIndex(bridgeIndex)
if err != nil {
return fmt.Errorf("Unable to find bridge %v: %v", bridgeIndex, err)
}
links, err := netlink.LinkList()
if err != nil {
return fmt.Errorf("Error listing interfaces: %v", err)
}
bridgeEmpty := true
for _, link := range links {
if link.Attrs().MasterIndex == bridge.Attrs().Index {
bridgeEmpty = false
log.Printf("[INFO] Link %s is still attached to bridge %s", link.Attrs().Name, bridge.Attrs().Name)
}
}
if bridgeEmpty == false {
return fmt.Errorf("Unable to delete bridge %s. Interfaces are still attached to it.", bridge.Attrs().Name)
} else {
if err := netlink.LinkDel(bridge); err != nil {
return fmt.Errorf("Error deleting bridge: %s", err)
}
}
return nil
}
func NewNetlinkMonitor(g canvas.Graph, r *Renderer, modules *bpf.BpfTable) (res *NetlinkMonitor, err error) {
nlmon := &NetlinkMonitor{
updates: make(chan netlink.LinkUpdate),
done: make(chan struct{}),
flush: make(chan struct{}),
nodes: make(map[int]*ExtInterface),
g: g,
r: r,
modules: modules,
}
err = netlink.LinkSubscribe(nlmon.updates, nlmon.done)
defer func() {
if err != nil {
nlmon.Close()
}
}()
if err != nil {
return
}
links, err := netlink.LinkList()
if err != nil {
return
}
for _, link := range links {
nlmon.handleNewlink(link)
}
Debug.Println("NewNetlinkMonitor DONE")
go nlmon.ParseLinkUpdates()
res = nlmon
return
}
func waitForIface() (netlink.Link, error) {
logrus.Debugf("Starting to wait for network interface")
start := time.Now()
for {
fmt.Printf(".")
if time.Since(start) > 5*time.Second {
fmt.Printf("\n")
return nil, fmt.Errorf("failed to find veth interface in 5 seconds")
}
// get list of all interfaces
lst, err := netlink.LinkList()
if err != nil {
fmt.Printf("\n")
return nil, err
}
for _, l := range lst {
// if we found "veth" interface - it's time to continue setup
if l.Type() == "veth" {
fmt.Printf("\n")
return l, nil
}
}
time.Sleep(100 * time.Millisecond)
}
}
func RunDhcp(netCfg *NetworkConfig, setHostname, setDns bool) error {
populateDefault(netCfg)
links, err := netlink.LinkList()
if err != nil {
return err
}
dhcpLinks := map[string]string{}
for _, link := range links {
if match, ok := findMatch(link, netCfg); ok && match.DHCP {
dhcpLinks[link.Attrs().Name] = match.DHCPArgs
}
}
//run dhcp
wg := sync.WaitGroup{}
for iface, args := range dhcpLinks {
wg.Add(1)
go func(iface, args string) {
runDhcp(netCfg, iface, args, setHostname, setDns)
wg.Done()
}(iface, args)
}
wg.Wait()
return err
}
// GetNetlinkAddrList returns a list of local IP addresses
func GetNetlinkAddrList() ([]string, error) {
var addrList []string
// get the link list
linkList, err := netlink.LinkList()
if err != nil {
return addrList, err
}
log.Debugf("Got link list(%d): %+v", len(linkList), linkList)
// Loop thru each interface and add its ip addr to list
for _, link := range linkList {
if strings.HasPrefix(link.Attrs().Name, "docker") || strings.HasPrefix(link.Attrs().Name, "veth") ||
strings.HasPrefix(link.Attrs().Name, "vport") || strings.HasPrefix(link.Attrs().Name, "lo") {
continue
}
addrs, err := netlink.AddrList(link, netlink.FAMILY_V4)
if err != nil {
return addrList, err
}
for _, addr := range addrs {
addrList = append(addrList, addr.IP.String())
}
}
return addrList, err
}
func ApplyNetworkConfigs(netCfg *NetworkConfig) error {
populateDefault(netCfg)
log.Debugf("Config: %#v", netCfg)
runCmds(netCfg.PreCmds, "")
createInterfaces(netCfg)
createSlaveInterfaces(netCfg)
links, err := netlink.LinkList()
if err != nil {
return err
}
//apply network config
for _, link := range links {
linkName := link.Attrs().Name
if match, ok := findMatch(link, netCfg); ok && !match.DHCP {
if err := applyInterfaceConfig(link, match); err != nil {
log.Errorf("Failed to apply settings to %s : %v", linkName, err)
}
}
}
runCmds(netCfg.PostCmds, "")
return err
}
// Search the network namespace of a process for interfaces matching a predicate
func FindNetDevs(procPath string, processID int, match func(string) bool) ([]NetDev, error) {
var netDevs []NetDev
ns, err := netns.GetFromPath(fmt.Sprintf("%s/%d/ns/net", procPath, processID))
if err != nil {
return nil, err
}
defer ns.Close()
err = WithNetNS(ns, func() error {
links, err := netlink.LinkList()
if err != nil {
return err
}
for _, link := range links {
if match(link.Attrs().Name) {
addrs, err := netlink.AddrList(link, netlink.FAMILY_V4)
if err != nil {
return err
}
netDev := NetDev{MAC: link.Attrs().HardwareAddr}
for _, addr := range addrs {
netDev.CIDRs = append(netDev.CIDRs, addr.IPNet)
}
netDevs = append(netDevs, netDev)
}
}
return nil
})
return netDevs, err
}
// Returns a list of routes
func RouteMap() *map[string]Route {
links, _ := netlink.LinkList()
linksMap := make(map[int]string)
for _, l := range links {
attrs := *l.Attrs()
linksMap[attrs.Index] = attrs.Name
}
routes := make(map[string]Route)
routeList, _ := netlink.RouteList(nil, netlink.FAMILY_V4)
for _, r := range routeList {
if_ := linksMap[r.LinkIndex]
rdst := r.Dst
var dst string
if rdst != nil {
dst = rdst.String()
} else {
dst = "default"
}
route := Route{
Via: r.Gw,
Dev: if_,
Src: r.Src,
}
routes[dst] = route
}
return &routes
}
func GetBridgeFromIndex(idx int) (string, error) {
var attr, bridge *netlink.LinkAttrs
links, err := netlink.LinkList()
if err != nil {
glog.Error(err)
return "", err
}
for _, link := range links {
if link.Type() != "veth" {
continue
}
if link.Attrs().Index == idx {
attr = link.Attrs()
break
}
}
if attr == nil {
return "", fmt.Errorf("cann't find nic whose ifindex is %d", idx)
}
for _, link := range links {
if link.Type() != "bridge" && link.Type() != "openvswitch" {
continue
}
if link.Attrs().Index == attr.MasterIndex {
bridge = link.Attrs()
break
}
}
if bridge == nil {
return "", fmt.Errorf("cann't find bridge contains nic whose ifindex is %d", idx)
}
if bridge.Name == "ovs-system" {
veth, err := netlink.LinkByIndex(idx)
if err != nil {
return "", err
}
out, err := exec.Command("ovs-vsctl", "port-to-br", veth.Attrs().Name).CombinedOutput()
if err != nil {
return "", err
}
bridge.Name = strings.TrimSpace(string(out))
}
glog.Infof("find bridge %s", bridge.Name)
return bridge.Name, nil
}
func (u *NetLinkProbe) initialize() {
links, err := netlink.LinkList()
if err != nil {
logging.GetLogger().Errorf("Unable to list interfaces: %s", err.Error())
return
}
for _, link := range links {
u.addLinkToTopology(link)
}
}
func linkListing() {
links, err := netlink.LinkList()
if err != nil {
panic(err)
}
fmt.Println("Interface listing:")
for _, link := range links {
fmt.Println(link.Attrs().Name)
}
}
func IsVethExists(vethHostName string) (bool, error) {
links, err := netlink.LinkList()
if err != nil {
return false, errors.Wrap(err, "Veth existing check error")
}
for _, link := range links {
if link.Attrs().Name == vethHostName {
return true, nil
}
}
return false, nil
}
func forEachLink(f func(netlink.Link) error) error {
links, err := netlink.LinkList()
if err != nil {
return err
}
for _, link := range links {
if err := f(link); err != nil {
return err
}
}
return nil
}
func (d *Driver) cleanup(netID string) {
links, err := d.getLinks(netID)
if err != nil {
log.Errorf("Error getting links: %v", err)
return
}
VxlanIndex := links.Vxlan.LinkAttrs.Index
allLinks, err := netlink.LinkList()
if err != nil {
log.Errorf("Error getting all links: %v", err)
return
}
// Do nothing if other interfaces are slaves of the vxlan interface
for _, link := range allLinks {
if link.Attrs().MasterIndex == VxlanIndex {
log.Debugf("Interface still attached to vxlan: %v", link)
return
}
}
// Do nothing if there are other containers in this network
netResource, err := d.docker.NetworkInspect(context.Background(), netID)
if err != nil {
log.Errorf("Error inspecting network: %v", err)
return
}
netName := netResource.Name
containers, err := d.docker.ContainerList(context.Background(), dockertypes.ContainerListOptions{})
if err != nil {
log.Errorf("Error getting containers: %v", err)
return
}
for _, container := range containers {
if _, ok := container.NetworkSettings.Networks[netName]; ok {
log.Debugf("Other containers are still connected to this network")
return
}
}
log.Debugf("No interfaces attached to vxlan: deleting vxlan interface.")
err = d.deleteNics(netID)
if err != nil {
log.Errorf("Error deleting nics: %v", err)
}
return
}
func (adapter *HostAdapter) Interfaces() <-chan Interface {
ch := make(chan Interface)
go func() {
defer close(ch)
links, err := netlink.LinkList()
if err != nil {
return
}
for _, link := range links {
ch <- &HostInterface{
id: link.Attrs().Index,
name: link.Attrs().Name,
}
}
}()
return ch
}
func getLinkIndex(ip net.IP) (int, error) {
links, err := netlink.LinkList()
if err != nil {
return -1, fmt.Errorf("Failed to get links")
}
for _, link := range links {
addrs, err := netlink.AddrList(link, netlink.FAMILY_ALL)
if err != nil {
return -1, fmt.Errorf("Failed to get addrs")
}
for _, addr := range addrs {
if addr.IP.Equal(ip) {
return link.Attrs().Index, nil
}
}
}
return -1, fmt.Errorf("Could not find address")
}
func ApplyNetworkConfigs(netCfg *NetworkConfig) error {
populateDefault(netCfg)
log.Debugf("Config: %#v", netCfg)
runCmds(netCfg.PreCmds, "")
createInterfaces(netCfg)
createSlaveInterfaces(netCfg)
links, err := netlink.LinkList()
if err != nil {
return err
}
dhcpLinks := map[string]string{}
//apply network config
for _, link := range links {
linkName := link.Attrs().Name
if match, ok := findMatch(link, netCfg); ok {
if match.DHCP {
dhcpLinks[link.Attrs().Name] = match.DHCPArgs
} else if err = applyInterfaceConfig(link, match); err != nil {
log.Errorf("Failed to apply settings to %s : %v", linkName, err)
}
}
}
//run dhcp
wg := sync.WaitGroup{}
for iface, args := range dhcpLinks {
wg.Add(1)
go func(iface, args string) {
runDhcp(iface, args)
wg.Done()
}(iface, args)
}
wg.Wait()
runCmds(netCfg.PostCmds, "")
return err
}
func deleteVxlanByVNI(vni uint32) error {
defer osl.InitOSContext()()
links, err := netlink.LinkList()
if err != nil {
return fmt.Errorf("failed to list interfaces while deleting vxlan interface by vni: %v", err)
}
for _, l := range links {
if l.Type() == "vxlan" && l.(*netlink.Vxlan).VxlanId == int(vni) {
err = netlink.LinkDel(l)
if err != nil {
return fmt.Errorf("error deleting vxlan interface with id %d: %v", vni, err)
}
return nil
}
}
return fmt.Errorf("could not find a vxlan interface to delete with id %d", vni)
}
func collectionInterfaceInfo() []supervisor.InterfaceInfo {
infos := []supervisor.InterfaceInfo{}
links, err := netlink.LinkList()
if err != nil {
glog.Error(err)
return infos
}
for _, link := range links {
if link.Type() != "veth" {
// lo is here too
continue
}
addrs, err := netlink.AddrList(link, netlink.FAMILY_V4)
if err != nil {
glog.Error(err)
return infos
}
for _, addr := range addrs {
info := supervisor.InterfaceInfo{
Ip: addr.IPNet.String(),
Index: link.Attrs().Index,
PeerIndex: link.Attrs().ParentIndex,
}
glog.Infof("get interface %v", info)
infos = append(infos, info)
}
// set link down, tap device take over it
netlink.LinkSetDown(link)
}
return infos
}
func (c *Cluster) resolveSystemAddr() (net.IP, error) {
// Use the system's only device IP address, or fail if there are
// multiple addresses to choose from.
interfaces, err := netlink.LinkList()
if err != nil {
return nil, err
}
var systemAddr net.IP
var systemInterface string
for _, intf := range interfaces {
// Skip non device or inactive interfaces
if intf.Type() != "device" || intf.Attrs().Flags&net.FlagUp == 0 {
continue
}
addrs, err := netlink.AddrList(intf, netlink.FAMILY_ALL)
if err != nil {
continue
}
var interfaceAddr4, interfaceAddr6 net.IP
for _, addr := range addrs {
ipAddr := addr.IPNet.IP
// Skip loopback and link-local addresses
if !ipAddr.IsGlobalUnicast() {
continue
}
if ipAddr.To4() != nil {
if interfaceAddr4 != nil {
return nil, errMultipleIPs(intf.Attrs().Name, intf.Attrs().Name, interfaceAddr4, ipAddr)
}
interfaceAddr4 = ipAddr
} else {
if interfaceAddr6 != nil {
return nil, errMultipleIPs(intf.Attrs().Name, intf.Attrs().Name, interfaceAddr6, ipAddr)
}
interfaceAddr6 = ipAddr
}
}
// In the case that this interface has exactly one IPv4 address
// and exactly one IPv6 address, favor IPv4 over IPv6.
if interfaceAddr4 != nil {
if systemAddr != nil {
return nil, errMultipleIPs(systemInterface, intf.Attrs().Name, systemAddr, interfaceAddr4)
}
systemAddr = interfaceAddr4
systemInterface = intf.Attrs().Name
} else if interfaceAddr6 != nil {
if systemAddr != nil {
return nil, errMultipleIPs(systemInterface, intf.Attrs().Name, systemAddr, interfaceAddr6)
}
systemAddr = interfaceAddr6
systemInterface = intf.Attrs().Name
}
}
if systemAddr == nil {
return nil, errNoIP
}
return systemAddr, nil
}
func (*nl) LinkList() ([]netlink.Link, error) {
return netlink.LinkList()
}
func (c *Cluster) resolveSystemAddr() (net.IP, error) {
// Use the system's only device IP address, or fail if there are
// multiple addresses to choose from.
interfaces, err := netlink.LinkList()
if err != nil {
return nil, err
}
var (
systemAddr net.IP
systemInterface string
deviceFound bool
)
for _, intf := range interfaces {
// Skip non device or inactive interfaces
if intf.Type() != "device" || intf.Attrs().Flags&net.FlagUp == 0 {
continue
}
addrs, err := netlink.AddrList(intf, netlink.FAMILY_ALL)
if err != nil {
continue
}
var interfaceAddr4, interfaceAddr6 net.IP
for _, addr := range addrs {
ipAddr := addr.IPNet.IP
// Skip loopback and link-local addresses
if !ipAddr.IsGlobalUnicast() {
continue
}
// At least one non-loopback device is found and it is administratively up
deviceFound = true
if ipAddr.To4() != nil {
if interfaceAddr4 != nil {
return nil, errMultipleIPs(intf.Attrs().Name, intf.Attrs().Name, interfaceAddr4, ipAddr)
}
interfaceAddr4 = ipAddr
} else {
if interfaceAddr6 != nil {
return nil, errMultipleIPs(intf.Attrs().Name, intf.Attrs().Name, interfaceAddr6, ipAddr)
}
interfaceAddr6 = ipAddr
}
}
// In the case that this interface has exactly one IPv4 address
// and exactly one IPv6 address, favor IPv4 over IPv6.
if interfaceAddr4 != nil {
if systemAddr != nil {
return nil, errMultipleIPs(systemInterface, intf.Attrs().Name, systemAddr, interfaceAddr4)
}
systemAddr = interfaceAddr4
systemInterface = intf.Attrs().Name
} else if interfaceAddr6 != nil {
if systemAddr != nil {
return nil, errMultipleIPs(systemInterface, intf.Attrs().Name, systemAddr, interfaceAddr6)
}
systemAddr = interfaceAddr6
systemInterface = intf.Attrs().Name
}
}
if systemAddr == nil {
if !deviceFound {
// If no non-loopback device type interface is found,
// fall back to the regular auto-detection mechanism.
// This is to cover the case where docker is running
// inside a container (eths are in fact veths).
return c.resolveSystemAddrViaSubnetCheck()
}
return nil, errNoIP
}
return systemAddr, nil
}
addrs, err := netlink.AddrList(link, syscall.AF_INET)
Expect(err).NotTo(HaveOccurred())
Expect(len(addrs)).To(BeNumerically(">", 0))
found := false
subnetPrefix, subnetBits := subnet.Mask.Size()
for _, a := range addrs {
aPrefix, aBits := a.IPNet.Mask.Size()
if a.IPNet.IP.Equal(gwaddr) && aPrefix == subnetPrefix && aBits == subnetBits {
found = true
break
}
}
Expect(found).To(Equal(true))
// Check for the veth link in the main namespace
links, err := netlink.LinkList()
Expect(err).NotTo(HaveOccurred())
Expect(len(links)).To(Equal(3)) // Bridge, veth, and loopback
for _, l := range links {
switch {
case l.Attrs().Name == BRNAME:
{
_, isBridge := l.(*netlink.Bridge)
Expect(isBridge).To(Equal(true))
hwAddr := fmt.Sprintf("%s", l.Attrs().HardwareAddr)
Expect(hwAddr).To(HavePrefix(hwaddr.PrivateMACPrefixString))
}
case l.Attrs().Name != BRNAME && l.Attrs().Name != "lo":
{
_, isVeth := l.(*netlink.Veth)
Expect(isVeth).To(Equal(true))
func ApplyNetworkConfigs(netCfg *config.NetworkConfig) error {
if err := createInterfaces(netCfg); err != nil {
return err
}
links, err := netlink.LinkList()
if err != nil {
return err
}
//apply network config
for _, link := range links {
linkName := link.Attrs().Name
var match config.InterfaceConfig
for key, netConf := range netCfg.Interfaces {
if netConf.Match == "" {
netConf.Match = key
}
if netConf.Match == "" {
continue
}
if len(netConf.Match) > 4 && strings.ToLower(netConf.Match[:3]) == "mac" {
haAddr, err := net.ParseMAC(netConf.Match[4:])
if err != nil {
return err
}
if bytes.Compare(haAddr, link.Attrs().HardwareAddr) == 0 {
// MAC address match is used over all other matches
match = netConf
break
}
}
// "" means match has not been found
if match.Match == "" && matches(linkName, netConf.Match) {
match = netConf
}
if netConf.Match == linkName {
// Found exact match, use it over wildcard match
match = netConf
}
}
if match.Match != "" {
err = applyNetConf(link, match)
if err != nil {
log.Errorf("Failed to apply settings to %s : %v", linkName, err)
}
}
}
if err != nil {
return err
}
//post run
if netCfg.PostRun != nil {
return docker.StartAndWait(config.DOCKER_SYSTEM_HOST, netCfg.PostRun)
}
return nil
}
func ApplyNetworkConfigs(netCfg *NetworkConfig) error {
log.Debugf("Config: %#v", netCfg)
if err := createInterfaces(netCfg); err != nil {
return err
}
links, err := netlink.LinkList()
if err != nil {
return err
}
dhcpLinks := []string{}
//apply network config
for _, link := range links {
linkName := link.Attrs().Name
var match InterfaceConfig
for key, netConf := range netCfg.Interfaces {
if netConf.Match == "" {
netConf.Match = key
}
if netConf.Match == "" {
continue
}
if len(netConf.Match) > 4 && strings.ToLower(netConf.Match[:3]) == "mac" {
haAddr, err := net.ParseMAC(netConf.Match[4:])
if err != nil {
return err
}
if bytes.Compare(haAddr, link.Attrs().HardwareAddr) == 0 {
// MAC address match is used over all other matches
match = netConf
break
}
}
// "" means match has not been found
if match.Match == "" && matches(linkName, netConf.Match) {
match = netConf
}
if netConf.Match == linkName {
// Found exact match, use it over wildcard match
match = netConf
}
}
if match.Match != "" {
if match.DHCP {
dhcpLinks = append(dhcpLinks, link.Attrs().Name)
} else if err = applyNetConf(link, match); err != nil {
log.Errorf("Failed to apply settings to %s : %v", linkName, err)
}
}
}
if len(dhcpLinks) > 0 {
log.Infof("Running DHCP on %v", dhcpLinks)
dhcpcdArgs := append([]string{"-MA4", "-e", "force_hostname=true"}, dhcpLinks...)
cmd := exec.Command("dhcpcd", dhcpcdArgs...)
cmd.Stdout = os.Stdout
cmd.Stderr = os.Stderr
if err := cmd.Run(); err != nil {
log.Error(err)
}
}
if err != nil {
return err
}
return nil
}
// configureNetwork handles iterating the local interfaces, matching it to an
// interface configuration, and configuring it. It will also handle configuring
// the default gateway after all interfaces are configured.
func (r *runner) configureNetwork() error {
r.log.Info("Configuring network...")
links, err := netlink.LinkList()
if err != nil {
return fmt.Errorf("failed to list network interfaces: %v", err)
}
for _, link := range links {
linkName := link.Attrs().Name
r.log.Debugf("Configuring %s...", linkName)
// look for a matching network config entry
var netconf *kurmaNetworkInterface
for _, n := range r.config.NetworkConfig.Interfaces {
if linkName == n.Device {
netconf = n
break
}
if match, _ := regexp.MatchString(n.Device, linkName); match {
netconf = n
break
}
}
// handle if none are found
if netconf == nil {
r.log.Warn("- no matching network configuraton found")
continue
}
// configure it
if err := configureInterface(link, netconf); err != nil {
r.log.Warnf("- %s", err.Error())
}
}
// configure the gateway
if r.config.NetworkConfig.Gateway != "" {
gateway := net.ParseIP(r.config.NetworkConfig.Gateway)
if gateway == nil {
r.log.Warnf("Failed to configure gatway to %q", r.config.NetworkConfig.Gateway)
}
route := &netlink.Route{
Scope: netlink.SCOPE_UNIVERSE,
Gw: gateway,
}
if err := netlink.RouteAdd(route); err != nil {
r.log.Warnf("Failed to configure gateway: %v", err)
return nil
}
r.log.Infof("Configured gatway to %s", r.config.NetworkConfig.Gateway)
}
// configure DNS
if len(r.config.NetworkConfig.DNS) > 0 {
// write the resolv.conf
if err := os.RemoveAll("/etc/resolv.conf"); err != nil {
r.log.Errorf("failed to cleanup old resolv.conf: %v", err)
return nil
}
f, err := os.OpenFile("/etc/resolv.conf", os.O_CREATE, os.FileMode(0644))
if err != nil {
r.log.Errorf("failed to open /etc/resolv.conf: %v", err)
return nil
}
defer f.Close()
for _, ns := range r.config.NetworkConfig.DNS {
if _, err := fmt.Fprintf(f, "nameserver %s\n", ns); err != nil {
r.log.Errorf("failed to write to resolv.conf: %v", err)
return nil
}
}
}
return nil
}