feat: mac address is persistent now

Signed-off-by: Armin Schlegel <armin.schlegel@gmx.de>
flannel-io · Dec 21, 2023 · 741366a · 741366a
1 parent 9fbcf29
commit 741366a
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Showing 5 changed files with 57 additions and 3 deletions.
diff --git a/pkg/backend/vxlan/device.go b/pkg/backend/vxlan/device.go
@@ -38,6 +38,7 @@ type vxlanDeviceAttrs struct {
 	vtepPort  int
 	gbp       bool
 	learning  bool
+	hwAddr    net.HardwareAddr
 }
 
 type vxlanDevice struct {
@@ -46,9 +47,13 @@ type vxlanDevice struct {
 }
 
 func newVXLANDevice(devAttrs *vxlanDeviceAttrs) (*vxlanDevice, error) {
-	hardwareAddr, err := mac.NewHardwareAddr()
-	if err != nil {
-		return nil, err
+	var err error
+	hardwareAddr := devAttrs.hwAddr
+	if devAttrs.hwAddr == nil {
+		hardwareAddr, err = mac.NewHardwareAddr()
+		if err != nil {
+			return nil, err
+		}
 	}
 
 	link := &netlink.Vxlan{

diff --git a/pkg/backend/vxlan/vxlan.go b/pkg/backend/vxlan/vxlan.go
@@ -142,6 +142,19 @@ func (be *VXLANBackend) RegisterNetwork(ctx context.Context, wg *sync.WaitGroup,
 
 	var dev, v6Dev *vxlanDevice
 	var err error
+
+	// When flannel is restarted, it will get the MAC address from the node annotations to set flannel.1 MAC address
+	var hwAddr net.HardwareAddr
+
+	macStr := be.subnetMgr.GetStoredMacAddress()
+	if macStr != "" {
+		hwAddr, err = net.ParseMAC(macStr)
+		if err != nil {
+			log.Errorf("Failed to parse mac addr(%s): %v", macStr, err)
+		}
+		log.Infof("Setup flannel.1 mac address to %s when flannel restarts", macStr)
+	}
+
 	if config.EnableIPv4 {
 		devAttrs := vxlanDeviceAttrs{
 			vni:       uint32(cfg.VNI),
@@ -152,6 +165,7 @@ func (be *VXLANBackend) RegisterNetwork(ctx context.Context, wg *sync.WaitGroup,
 			vtepPort:  cfg.Port,
 			gbp:       cfg.GBP,
 			learning:  cfg.Learning,
+			hwAddr:    hwAddr,
 		}
 
 		dev, err = newVXLANDevice(&devAttrs)
@@ -170,6 +184,7 @@ func (be *VXLANBackend) RegisterNetwork(ctx context.Context, wg *sync.WaitGroup,
 			vtepPort:  cfg.Port,
 			gbp:       cfg.GBP,
 			learning:  cfg.Learning,
+			hwAddr:    nil,
 		}
 		v6Dev, err = newVXLANDevice(&v6DevAttrs)
 		if err != nil {

diff --git a/pkg/subnet/etcd/local_manager.go b/pkg/subnet/etcd/local_manager.go
@@ -79,6 +79,10 @@ func newLocalManager(r Registry, prevSubnet ip.IP4Net, prevIPv6Subnet ip.IP6Net,
 	}
 }
 
+func (m *LocalManager) GetStoredMacAddress() string {
+	return ""
+}
+
 func (m *LocalManager) GetNetworkConfig(ctx context.Context) (*subnet.Config, error) {
 	cfg, err := m.registry.getNetworkConfig(ctx)
 	if err != nil {

diff --git a/pkg/subnet/kube/kube.go b/pkg/subnet/kube/kube.go
@@ -21,6 +21,7 @@ import (
 	"net"
 	"os"
 	"strconv"
+	"strings"
 	"sync"
 	"time"
 
@@ -65,6 +66,7 @@ type kubeSubnetManager struct {
 	enableIPv4                bool
 	enableIPv6                bool
 	annotations               annotations
+	annotationPrefix          string
 	client                    clientset.Interface
 	nodeName                  string
 	nodeStore                 listers.NodeLister
@@ -160,6 +162,7 @@ func NewSubnetManager(ctx context.Context, apiUrl, kubeconfig, prefix, netConfPa
 func newKubeSubnetManager(ctx context.Context, c clientset.Interface, sc *subnet.Config, nodeName, prefix string, useMultiClusterCidr bool) (*kubeSubnetManager, error) {
 	var err error
 	var ksm kubeSubnetManager
+	ksm.annotationPrefix = prefix
 	ksm.annotations, err = newAnnotations(prefix)
 	if err != nil {
 		return nil, err
@@ -634,3 +637,29 @@ func (m *kubeSubnetManager) HandleSubnetFile(path string, config *subnet.Config,
 	}
 	return subnet.WriteSubnetFile(path, config, ipMasq, sn, ipv6sn, mtu)
 }
+
+// GetStoredMacAddress reads MAC address from node annotations when flannel restarts
+func (ksm *kubeSubnetManager) GetStoredMacAddress() string {
+	// get mac info from Name func.
+	node, err := ksm.client.CoreV1().Nodes().Get(context.TODO(), ksm.nodeName, metav1.GetOptions{})
+	if err != nil {
+		log.Errorf("Failed to get node for backend data: %v", err)
+		return ""
+	}
+
+	// node backend data format: `{"VNI":1,"VtepMAC":"12:c6:65:89:b4:e3"}`
+	// and we will return only mac addr str like 12:c6:65:89:b4:e3
+	if node != nil && node.Annotations != nil {
+		log.Infof("List of node(%s) annotations: %#+v", ksm.nodeName, node.Annotations)
+		backendData, ok := node.Annotations[fmt.Sprintf("%s/backend-data", ksm.annotationPrefix)]
+		if ok {
+			macStr := strings.Trim(backendData, "\"}")
+			macInfoSlice := strings.Split(macStr, ":\"")
+			if len(macInfoSlice) == 2 {
+				return macInfoSlice[1]
+			}
+		}
+	}
+
+	return ""
+}
diff --git a/pkg/subnet/subnet.go b/pkg/subnet/subnet.go
@@ -123,6 +123,7 @@ type Manager interface {
 	WatchLeases(ctx context.Context, receiver chan []lease.LeaseWatchResult) error
 	CompleteLease(ctx context.Context, lease *lease.Lease, wg *sync.WaitGroup) error
 
+	GetStoredMacAddress() string
 	Name() string
 }