Remove VPN_PMTUD option

Dockerfile

@@ -77,7 +77,6 @@ ENV VPN_SERVICE_PROVIDER=pia \
     VPN_TYPE=openvpn \
     # Common VPN options
     VPN_INTERFACE=tun0 \
-    VPN_PMTUD=on \
     # OpenVPN
     OPENVPN_ENDPOINT_IP= \
     OPENVPN_ENDPOINT_PORT= \

internal/configuration/settings/vpn.go

@@ -18,7 +18,6 @@ type VPN struct {
 	Provider  Provider  `json:"provider"`
 	OpenVPN   OpenVPN   `json:"openvpn"`
 	Wireguard Wireguard `json:"wireguard"`
-	PMTUD     *bool     `json:"pmtud"`
 }
 
 // TODO v4 remove pointer for receiver (because of Surfshark).
@@ -55,7 +54,6 @@ func (v *VPN) Copy() (copied VPN) {
 		Provider:  v.Provider.copy(),
 		OpenVPN:   v.OpenVPN.copy(),
 		Wireguard: v.Wireguard.copy(),
-		PMTUD:     gosettings.CopyPointer(v.PMTUD),
 	}
 }
 
@@ -64,7 +62,6 @@ func (v *VPN) OverrideWith(other VPN) {
 	v.Provider.overrideWith(other.Provider)
 	v.OpenVPN.overrideWith(other.OpenVPN)
 	v.Wireguard.overrideWith(other.Wireguard)
-	v.PMTUD = gosettings.OverrideWithPointer(v.PMTUD, other.PMTUD)
 }
 
 func (v *VPN) setDefaults() {
@@ -72,7 +69,6 @@ func (v *VPN) setDefaults() {
 	v.Provider.setDefaults()
 	v.OpenVPN.setDefaults(v.Provider.Name)
 	v.Wireguard.setDefaults(v.Provider.Name)
-	v.PMTUD = gosettings.DefaultPointer(v.PMTUD, true)
 }
 
 func (v VPN) String() string {
@@ -90,8 +86,6 @@ func (v VPN) toLinesNode() (node *gotree.Node) {
 		node.AppendNode(v.Wireguard.toLinesNode())
 	}
 
-	node.Appendf("Path MTU discovery update: %s", gosettings.BoolToYesNo(v.PMTUD))
-
 	return node
 }
 
@@ -113,10 +107,5 @@ func (v *VPN) read(r *reader.Reader) (err error) {
 		return fmt.Errorf("wireguard: %w", err)
 	}
 
-	v.PMTUD, err = r.BoolPtr("VPN_PMTUD")
-	if err != nil {
-		return err
-	}
-
 	return nil
 }

internal/vpn/run.go

@@ -47,7 +47,6 @@ func (l *Loop) Run(ctx context.Context, done chan<- struct{}) {
 			continue
 		}
 		tunnelUpData := tunnelUpData{
-			PMTUD:          *settings.PMTUD,
 			serverIP:       connection.IP,
 			vpnType:        settings.Type,
 			serverName:     connection.ServerName,

internal/vpn/tunnelup.go

@@ -18,10 +18,6 @@ type tunnelUpData struct {
 	// vpnIntf is the name of the VPN network interface
 	// which is used both for port forwarding and MTU discovery
 	vpnIntf string
-	// Path MTU discovery fields:
-	// PMTUD indicates whether to perform Path MTU Discovery and
-	// adjust the VPN interface MTU accordingly.
-	PMTUD bool
 	// serverIP is used for path MTU discovery
 	serverIP netip.Addr
 	// vpnType is used for path MTU discovery to find the protocol overhead.
@@ -38,14 +34,12 @@ type tunnelUpData struct {
 func (l *Loop) onTunnelUp(ctx context.Context, data tunnelUpData) {
 	l.client.CloseIdleConnections()
 
-	if data.PMTUD {
-		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)
-		if err != nil {
-			l.logger.Error(err.Error())
-		}
+	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)
+	if err != nil {
+		l.logger.Error(err.Error())
 	}
 
 	for _, vpnPort := range l.vpnInputPorts {
@@ -64,7 +58,7 @@ func (l *Loop) onTunnelUp(ctx context.Context, data tunnelUpData) {
 		}
 	}
 
-	err := l.publicip.RunOnce(ctx)
+	err = l.publicip.RunOnce(ctx)
 	if err != nil {
 		l.logger.Error("getting public IP address information: " + err.Error())
 	}