diff --git a/internal/bbr/devices/olt.go b/internal/bbr/devices/olt.go
index 5e68fa3..61af90a 100644
--- a/internal/bbr/devices/olt.go
+++ b/internal/bbr/devices/olt.go
@@ -52,6 +52,9 @@
 
 	for _, pon := range o.Olt.Pons {
 		for _, onu := range pon.Onus {
+			if err := onu.InternalState.Event("initialize"); err != nil {
+				log.Fatalf("Error initializing ONU: %v", err)
+			}
 			log.Tracef("Created ONU: %s (%d:%d)", onu.Sn(), onu.STag, onu.CTag)
 		}
 	}
diff --git a/internal/bbsim/devices/olt.go b/internal/bbsim/devices/olt.go
index 3264bc3..eabbe62 100644
--- a/internal/bbsim/devices/olt.go
+++ b/internal/bbsim/devices/olt.go
@@ -144,9 +144,11 @@
 		olt.Pons = append(olt.Pons, &p)
 	}
 
-	if err := olt.InternalState.Event("initialize"); err != nil {
-		log.Errorf("Error initializing OLT: %v", err)
-		return nil
+	if isMock != true {
+		if err := olt.InternalState.Event("initialize"); err != nil {
+			log.Errorf("Error initializing OLT: %v", err)
+			return nil
+		}
 	}
 
 	return &olt