Fix downtime on NAT client startup (#288)

fix missing traffic on NAT client startup Signed-off-by: terashima <[email protected]> Signed-off-by: Tomoki Sugiura <[email protected]> --------- Signed-off-by: terashima <[email protected]> Signed-off-by: Tomoki Sugiura <[email protected]> Co-authored-by: Tomoki Sugiura <[email protected]>
cybozu-go · May 27, 2024 · b78fcd7 · b78fcd7
1 parent 5faaa12
commit b78fcd7
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Showing 3 changed files with 13 additions and 4 deletions.
diff --git a/v2/pkg/founat/client.go b/v2/pkg/founat/client.go
@@ -386,6 +386,12 @@ func (c *natClient) addEgress1(link netlink.Link, n *net.IPNet) error {
 		priv = c.v6priv
 	}
 
+	// link up here to minimize the down time
+	// See https://github.com/cybozu-go/coil/issues/287.
+	if err := netlink.LinkSetUp(link); err != nil {
+		return fmt.Errorf("netlink: failed to link up %s: %w", link.Attrs().Name, err)
+	}
+
 	for _, p := range priv {
 		if !p.Contains(n.IP) {
 			continue
@@ -398,7 +404,7 @@ func (c *natClient) addEgress1(link netlink.Link, n *net.IPNet) error {
 			Protocol:  ncProtocolID,
 		})
 		if err != nil {
-			return fmt.Errorf("netlink: failed to add route to %s: %w", n.String(), err)
+			return fmt.Errorf("netlink: failed to add route(table %d) to %s: %w", ncNarrowTableID, n.String(), err)
 		}
 		return nil
 	}
@@ -410,7 +416,7 @@ func (c *natClient) addEgress1(link netlink.Link, n *net.IPNet) error {
 		Protocol:  ncProtocolID,
 	})
 	if err != nil {
-		return fmt.Errorf("netlink: failed to add route to %s: %w", n.String(), err)
+		return fmt.Errorf("netlink: failed to add route(table %d) to %s: %w", ncWideTableID, n.String(), err)
 	}
 	return nil
 }
diff --git a/v2/pkg/founat/egress.go b/v2/pkg/founat/egress.go
@@ -139,6 +139,11 @@ func (e *egress) AddClient(addr net.IP, link netlink.Link) error {
 		}
 	}
 
+	// link up here to minimize the down time
+	// See https://github.com/cybozu-go/coil/issues/287.
+	if err := netlink.LinkSetUp(link); err != nil {
+		return fmt.Errorf("netlink: failed to link up %s: %w", link.Attrs().Name, err)
+	}
 	err = netlink.RouteAdd(&netlink.Route{
 		Dst:       netlink.NewIPNet(addr),
 		LinkIndex: link.Attrs().Index,

diff --git a/v2/pkg/founat/fou.go b/v2/pkg/founat/fou.go
@@ -241,7 +241,6 @@ func (t *fouTunnel) addOrRecreatePeer4(addr net.IP, sportAuto bool) (string, err
 
 	attrs := netlink.NewLinkAttrs()
 	attrs.Name = linkName
-	attrs.Flags = net.FlagUp
 	encapSport := uint16(t.port)
 	if sportAuto {
 		encapSport = 0
@@ -311,7 +310,6 @@ func (t *fouTunnel) addOrRecreatePeer6(addr net.IP, sportAuto bool) (string, err
 
 	attrs := netlink.NewLinkAttrs()
 	attrs.Name = linkName
-	attrs.Flags = net.FlagUp
 	encapSport := uint16(t.port)
 	if sportAuto {
 		encapSport = 0