diff --git a/internal/vpn/run.go b/internal/vpn/run.go
index 65b44fac..971e76c0 100644
--- a/internal/vpn/run.go
+++ b/internal/vpn/run.go
@@ -47,7 +47,6 @@ func (l *Loop) Run(ctx context.Context, done chan<- struct{}) {
 			continue
 		}
 		tunnelUpData := tunnelUpData{
-			serverIP:       connection.IP,
 			vpnType:        settings.Type,
 			serverName:     connection.ServerName,
 			canPortForward: connection.PortForward,
diff --git a/internal/vpn/tunnelup.go b/internal/vpn/tunnelup.go
index e5c82ce3..3bba4dc0 100644
--- a/internal/vpn/tunnelup.go
+++ b/internal/vpn/tunnelup.go
@@ -4,7 +4,6 @@ import (
 	"context"
 	"errors"
 	"fmt"
-	"net/netip"
 	"time"
 
 	"github.com/qdm12/dns/v2/pkg/check"
@@ -18,8 +17,6 @@ type tunnelUpData struct {
 	// vpnIntf is the name of the VPN network interface
 	// which is used both for port forwarding and MTU discovery
 	vpnIntf string
-	// serverIP is used for path MTU discovery
-	serverIP netip.Addr
 	// vpnType is used for path MTU discovery to find the protocol overhead.
 	// It can be "wireguard" or "openvpn".
 	vpnType string
@@ -35,11 +32,10 @@ func (l *Loop) onTunnelUp(ctx context.Context, data tunnelUpData) {
 	l.client.CloseIdleConnections()
 
 	mtuLogger := l.logger.New(log.SetComponent("MTU discovery"))
-	mtuLogger.Info("finding maximum MTU, this can take up to 4 seconds")
-	err := updateToMaxMTU(ctx, data.vpnIntf, data.serverIP, data.vpnType,
-		l.netLinker, mtuLogger)
+	err := updateToMaxMTU(ctx, data.vpnIntf, data.vpnType,
+		l.netLinker, l.routing, mtuLogger)
 	if err != nil {
-		l.logger.Error(err.Error())
+		mtuLogger.Error(err.Error())
 	}
 
 	for _, vpnPort := range l.vpnInputPorts {
@@ -82,8 +78,15 @@ func (l *Loop) onTunnelUp(ctx context.Context, data tunnelUpData) {
 var errVPNTypeUnknown = errors.New("unknown VPN type")
 
 func updateToMaxMTU(ctx context.Context, vpnInterface string,
-	serverIP netip.Addr, vpnType string, netlinker NetLinker, logger *log.Logger,
+	vpnType string, netlinker NetLinker, routing Routing, logger *log.Logger,
 ) error {
+	logger.Info("finding maximum MTU, this can take up to 4 seconds")
+
+	vpnGatewayIP, err := routing.VPNLocalGatewayIP(vpnInterface)
+	if err != nil {
+		return fmt.Errorf("getting VPN gateway IP address: %w", err)
+	}
+
 	link, err := netlinker.LinkByName(vpnInterface)
 	if err != nil {
 		return fmt.Errorf("getting VPN interface by name: %w", err)
@@ -114,7 +117,7 @@ func updateToMaxMTU(ctx context.Context, vpnInterface string,
 	}
 
 	const pingTimeout = time.Second
-	vpnLinkMTU, err = pmtud.PathMTUDiscover(ctx, serverIP, vpnLinkMTU, pingTimeout, logger)
+	vpnLinkMTU, err = pmtud.PathMTUDiscover(ctx, vpnGatewayIP, vpnLinkMTU, pingTimeout, logger)
 	switch {
 	case err == nil:
 		logger.Infof("Setting VPN interface %s MTU to maximum valid MTU %d", vpnInterface, vpnLinkMTU)