Add error code handling

client/internal/peer/conn.go

@@ -2,6 +2,7 @@ package peer
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"math/rand"
 	"net"
@@ -209,7 +210,11 @@ func (conn *Conn) Open(engineCtx context.Context) error {
 	// both peer send offer
 	if err := conn.handshaker.SendOffer(); err != nil {
 		conn.Log.Errorf("failed to send offer: %v", err)
-		conn.guard.FailedToSendOffer()
+		// if remote peer is offline, no need to try to reconnect.
+		// The remote peer when online will send an offer to us
+		if !errors.Is(err, ErrPeerNotAvailable) {
+			conn.guard.FailedToSendOffer()
+		}
 	}
 
 	conn.opened = true

client/internal/peer/signaler.go

@@ -1,6 +1,8 @@
 package peer
 
 import (
+	"errors"
+
 	"github.com/pion/ice/v4"
 	log "github.com/sirupsen/logrus"
 	"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
@@ -9,6 +11,8 @@ import (
 	sProto "github.com/netbirdio/netbird/shared/signal/proto"
 )
 
+var ErrPeerNotAvailable = signal.ErrPeerNotAvailable
+
 type Signaler struct {
 	signal       signal.Client
 	wgPrivateKey wgtypes.Key
@@ -68,6 +72,9 @@ func (s *Signaler) signalOfferAnswer(offerAnswer OfferAnswer, remoteKey string,
 	}
 
 	if err = s.signal.SendWithDeliveryCheck(msg); err != nil {
+		if errors.Is(err, signal.ErrPeerNotAvailable) {
+			return ErrPeerNotAvailable
+		}
 		return err
 	}