diff --git a/common/config/libconfig/config_libconfig.c b/common/config/libconfig/config_libconfig.c
index ec57b420dd..48893fb5be 100644
--- a/common/config/libconfig/config_libconfig.c
+++ b/common/config/libconfig/config_libconfig.c
@@ -91,7 +91,7 @@ int read_intarray(paramdef_t *cfgoptions,config_setting_t *setting, char *cfgpat
 
 
 
-static int config_libconfig_get(paramdef_t *cfgoptions,int numoptions, char *prefix ) {
+int config_libconfig_get(paramdef_t *cfgoptions,int numoptions, char *prefix ) {
   config_setting_t *setting;
   char *str;
   int i,u;
@@ -122,7 +122,7 @@ static int config_libconfig_get(paramdef_t *cfgoptions,int numoptions, char *pre
 
     switch(cfgoptions[i].type) {
       case TYPE_STRING:
-        if ( config_lookup_string(&(libconfig_privdata.cfg), cfgpath, &str)) {
+        if ( config_lookup_string(&(libconfig_privdata.cfg), cfgpath, (const char**)&str)) {
           if ( cfgoptions[i].numelt > 0  && str != NULL && strlen(str) >= cfgoptions[i].numelt ) {
             fprintf(stderr,"[LIBCONFIG] %s:  %s exceeds maximum length of %i bytes, value truncated\n",
                     cfgpath,str,cfgoptions[i].numelt);
diff --git a/openair2/F1AP/f1ap_du_ue_context_management.c b/openair2/F1AP/f1ap_du_ue_context_management.c
index f1a10156a4..0986b1fd90 100644
--- a/openair2/F1AP/f1ap_du_ue_context_management.c
+++ b/openair2/F1AP/f1ap_du_ue_context_management.c
@@ -153,7 +153,7 @@ int DU_handle_UE_CONTEXT_SETUP_REQUEST(instance_t       instance,
       rnti_t ue_rnti = (f1ap_ue_context_setup_req->gNB_DU_ue_id!=NULL) ?
           f1ap_get_rnti_by_du_id(false, instance, *f1ap_ue_context_setup_req->gNB_DU_ue_id):
           f1ap_get_rnti_by_cu_id(false, instance, f1ap_ue_context_setup_req->gNB_CU_ue_id);
-      teid_t t=newGtpuCreateTunnel(instance,
+      teid_t t=newGtpuCreateTunnel(INSTANCE_DEFAULT,
                                    ue_rnti,
 				   drb_p->drb_id ,
 				   drb_p->drb_id,
diff --git a/openair2/GNB_APP/gnb_app.c b/openair2/GNB_APP/gnb_app.c
index cd041aabe4..94b0820d08 100644
--- a/openair2/GNB_APP/gnb_app.c
+++ b/openair2/GNB_APP/gnb_app.c
@@ -240,6 +240,8 @@ void *gNB_app_task(void *args_p)
       RCconfig_NR_DU_F1(msg_p, 0);
       
       itti_send_msg_to_task (TASK_DU_F1, GNB_MODULE_ID_TO_INSTANCE(0), msg_p);
+      //start F1-U
+      RCconfig_nr_gtpu(); 
     }
   }
   do {
diff --git a/openair3/ocp-gtpu/gtp_itf.cpp b/openair3/ocp-gtpu/gtp_itf.cpp
index e3dbfe0f25..f53e5d8cd6 100644
--- a/openair3/ocp-gtpu/gtp_itf.cpp
+++ b/openair3/ocp-gtpu/gtp_itf.cpp
@@ -139,10 +139,11 @@ static  int gtpv1uCreateAndSendMsg(int h, uint32_t peerIp, uint16_t peerPort, te
   to.sin_addr.s_addr = peerIp ;
   LOG_D(GTPU,"sending packet size: %d to %s\n",fullSize, inet_ntoa(to.sin_addr) );
 
-  if (sendto(h, (void *)buffer, (size_t)fullSize, 0,(struct sockaddr *)&to, sizeof(to) ) != fullSize ) {
+  int ret;
+  if ((ret=sendto(h, (void *)buffer, (size_t)fullSize, 0,(struct sockaddr *)&to, sizeof(to) )) != fullSize ) {
     LOG_E(GTPU,
-          "[SD %d] Failed to send data to " IPV4_ADDR " on port %d, buffer size %u\n",
-          h, IPV4_ADDR_FORMAT(peerIp), peerPort, fullSize);
+          "[SD %d] Failed to send data to " IPV4_ADDR " on port %d, buffer size %u, ret: %d, errno: %d\n",
+          h, IPV4_ADDR_FORMAT(peerIp), peerPort, fullSize, ret, errno);
     free(buffer);
     return GTPNOK;
   }
@@ -390,6 +391,7 @@ instance_t ocp_gtpv1Init(openAddr_t context) {
 teid_t newGtpuCreateTunnel(instance_t instance, rnti_t rnti, int incoming_bearer_id, int outgoing_bearer_id, teid_t outgoing_teid,
                            transport_layer_addr_t remoteAddr, int port, gtpCallback callBack) {
   pthread_mutex_lock(&globGtp.gtp_lock);
+  instance=compatInst(instance);
   auto inst=&globGtp.instances[instance];
   auto it=inst->ue2te_mapping.find(rnti);
 
@@ -465,7 +467,7 @@ int ocp_gtpv1u_create_s1u_tunnel(instance_t instance,
                 "From legacy code not clear, seems impossible (bearer=%d)\n",
                 create_tunnel_req->eps_bearer_id[i]);
     int incoming_rb_id=create_tunnel_req->eps_bearer_id[i]-4;
-    teid_t teid=newGtpuCreateTunnel(compatInst(instance), create_tunnel_req->rnti,
+    teid_t teid=newGtpuCreateTunnel(instance, create_tunnel_req->rnti,
                                     incoming_rb_id,
                                     create_tunnel_req->eps_bearer_id[i],
                                     create_tunnel_req->sgw_S1u_teid[i],
@@ -527,7 +529,7 @@ int gtpv1u_create_ngu_tunnel(  const instance_t instance,
         create_tunnel_req->outgoing_teid[0]);
 
   for (int i = 0; i < create_tunnel_req->num_tunnels; i++) {
-    teid_t teid=newGtpuCreateTunnel(compatInst(instance), create_tunnel_req->rnti,
+    teid_t teid=newGtpuCreateTunnel(instance, create_tunnel_req->rnti,
                                     create_tunnel_req->incoming_rb_id[i],
                                     create_tunnel_req->pdusession_id[i],
                                     create_tunnel_req->outgoing_teid[i],