diff --git a/include/osmocom/msc/vlr.h b/include/osmocom/msc/vlr.h
index b328b70..83c8e1b 100644
--- a/include/osmocom/msc/vlr.h
+++ b/include/osmocom/msc/vlr.h
@@ -65,6 +65,8 @@
 	VLR_ULA_E_ID_IMSI,	/* IMSI recieved from MS */
 	VLR_ULA_E_ID_IMEI,	/* IMEI received from MS */
 	VLR_ULA_E_ID_IMEISV,	/* IMEISV received from MS */
+	VLR_ULA_E_HLR_IMEI_ACK,	/* Check_IMEI_VLR result from HLR */
+	VLR_ULA_E_HLR_IMEI_NACK,/* Check_IMEI_VLR result from HLR */
 	VLR_ULA_E_HLR_LU_RES,	/* HLR UpdateLocation result */
 	VLR_ULA_E_UPD_HLR_COMPL,/* UpdatE_HLR_VLR result */
 	VLR_ULA_E_LU_COMPL_SUCCESS,/* Location_Update_Completion_VLR result */
diff --git a/src/libvlr/vlr.c b/src/libvlr/vlr.c
index 887602c..451c521 100644
--- a/src/libvlr/vlr.c
+++ b/src/libvlr/vlr.c
@@ -657,6 +657,28 @@
 	return vlr_subscr_tx_gsup_message(vsub, &gsup_msg);
 }
 
+/* Initiate Check_IMEI_VLR Procedure (23.018 Chapter 7.1.2.9) */
+int vlr_subscr_tx_req_check_imei(const struct vlr_subscr *vsub)
+{
+	struct osmo_gsup_message gsup_msg = {0};
+	uint8_t imei_enc[GSM23003_IMEI_NUM_DIGITS+2]; /* +2: IE header */
+	int len;
+
+	/* Encode IMEI */
+	len = gsm48_encode_bcd_number(imei_enc, sizeof(imei_enc), 0, vsub->imei);
+	if (len < 1) {
+		LOGVSUBP(LOGL_ERROR, vsub, "Error: cannot encode IMEI '%s'\n", vsub->imei);
+		return -ENOSPC;
+	}
+	gsup_msg.imei_enc = imei_enc;
+	gsup_msg.imei_enc_len = len;
+
+	/* Send CHECK_IMEI_REQUEST */
+	gsup_msg.message_type = OSMO_GSUP_MSGT_CHECK_IMEI_REQUEST;
+	OSMO_STRLCPY_ARRAY(gsup_msg.imsi, vsub->imsi);
+	return vlr_tx_gsup_message(vsub->vlr, &gsup_msg);
+}
+
 /* Tell HLR that authentication failure occurred */
 int vlr_subscr_tx_auth_fail_rep(const struct vlr_subscr *vsub)
 {
@@ -991,6 +1013,29 @@
 	return rc;
 }
 
+/* Handle Check_IMEI_VLR result and error from HLR */
+static int vlr_subscr_handle_check_imei(struct vlr_subscr *vsub, const struct osmo_gsup_message *gsup)
+{
+	if (!vsub->lu_fsm) {
+		LOGVSUBP(LOGL_ERROR, vsub, "Rx %s without LU in progress\n",
+			 osmo_gsup_message_type_name(gsup->message_type));
+		return -ENODEV;
+	}
+
+	if (gsup->message_type == OSMO_GSUP_MSGT_CHECK_IMEI_RESULT) {
+		if (gsup->imei_result == OSMO_GSUP_IMEI_RESULT_ACK)
+			osmo_fsm_inst_dispatch(vsub->lu_fsm, VLR_ULA_E_HLR_IMEI_ACK, NULL);
+		else
+			osmo_fsm_inst_dispatch(vsub->lu_fsm, VLR_ULA_E_HLR_IMEI_NACK, NULL);
+	} else {
+		LOGVSUBP(LOGL_ERROR, vsub, "Check_IMEI_VLR failed; gmm_cause: %s\n",
+			 get_value_string(gsm48_gmm_cause_names, gsup->cause));
+		osmo_fsm_inst_dispatch(vsub->lu_fsm, VLR_ULA_E_HLR_IMEI_NACK, NULL);
+	}
+
+	return 0;
+}
+
 /* Incoming handler for GSUP from HLR.
  * Keep this function non-static for direct invocation by unit tests. */
 int vlr_gsupc_read_cb(struct osmo_gsup_client *gsupc, struct msgb *msg)
@@ -1060,6 +1105,10 @@
 			gsup.message_type);
 		rc = -GMM_CAUSE_MSGT_NOTEXIST_NOTIMPL;
 		break;
+	case OSMO_GSUP_MSGT_CHECK_IMEI_ERROR:
+	case OSMO_GSUP_MSGT_CHECK_IMEI_RESULT:
+		rc = vlr_subscr_handle_check_imei(vsub, &gsup);
+		break;
 	default:
 		/* Forward message towards MSC */
 		rc = vlr->ops.forward_gsup_msg(vsub, &gsup);
diff --git a/src/libvlr/vlr_core.h b/src/libvlr/vlr_core.h
index c249dff..41b8800 100644
--- a/src/libvlr/vlr_core.h
+++ b/src/libvlr/vlr_core.h
@@ -7,5 +7,6 @@
 int vlr_subscr_req_lu(struct vlr_subscr *vsub) __attribute__((warn_unused_result));
 int vlr_subscr_req_sai(struct vlr_subscr *vsub, const uint8_t *auts,
 		       const uint8_t *auts_rand) __attribute__((warn_unused_result));
+int vlr_subscr_tx_req_check_imei(const struct vlr_subscr *vsub);
 void vlr_subscr_update_tuples(struct vlr_subscr *vsub,
 			      const struct osmo_gsup_message *gsup);
diff --git a/src/libvlr/vlr_lu_fsm.c b/src/libvlr/vlr_lu_fsm.c
index 8640d2b..a97e97a 100644
--- a/src/libvlr/vlr_lu_fsm.c
+++ b/src/libvlr/vlr_lu_fsm.c
@@ -653,6 +653,8 @@
 	OSMO_VALUE_STRING(VLR_ULA_E_ID_IMSI),
 	OSMO_VALUE_STRING(VLR_ULA_E_ID_IMEI),
 	OSMO_VALUE_STRING(VLR_ULA_E_ID_IMEISV),
+	OSMO_VALUE_STRING(VLR_ULA_E_HLR_IMEI_ACK),
+	OSMO_VALUE_STRING(VLR_ULA_E_HLR_IMEI_NACK),
 	OSMO_VALUE_STRING(VLR_ULA_E_HLR_LU_RES),
 	OSMO_VALUE_STRING(VLR_ULA_E_UPD_HLR_COMPL),
 	OSMO_VALUE_STRING(VLR_ULA_E_LU_COMPL_SUCCESS),
@@ -1229,9 +1231,17 @@
 				       LU_COMPL_VLR_E_NEW_TMSI_ACK, NULL);
 		break;
 	case VLR_ULA_E_ID_IMEI:
+		/* Got the IMEI from ME, now send it to HLR */
+		vlr_subscr_tx_req_check_imei(lfp->vsub);
+		break;
+	case VLR_ULA_E_HLR_IMEI_ACK:
 		osmo_fsm_inst_dispatch(lfp->lu_compl_vlr_fsm,
 				       LU_COMPL_VLR_E_IMEI_CHECK_ACK, NULL);
 		break;
+	case VLR_ULA_E_HLR_IMEI_NACK:
+		osmo_fsm_inst_dispatch(lfp->lu_compl_vlr_fsm,
+				       LU_COMPL_VLR_E_IMEI_CHECK_NACK, NULL);
+		break;
 	case VLR_ULA_E_LU_COMPL_SUCCESS:
 		lu_fsm_discard_lu_compl_fsm(fi);
 
@@ -1362,7 +1372,9 @@
 				 S(VLR_ULA_E_LU_COMPL_FAILURE) |
 				 S(VLR_ULA_E_NEW_TMSI_ACK) |
 				 S(VLR_ULA_E_ID_IMEI) |
-				 S(VLR_ULA_E_ID_IMEISV),
+				 S(VLR_ULA_E_ID_IMEISV) |
+				 S(VLR_ULA_E_HLR_IMEI_ACK) |
+				 S(VLR_ULA_E_HLR_IMEI_NACK),
 		.out_state_mask = S(VLR_ULA_S_DONE),
 		.name = OSMO_STRINGIFY(VLR_ULA_S_WAIT_LU_COMPL),
 		.action = lu_fsm_wait_lu_compl,
diff --git a/tests/msc_vlr/msc_vlr_test_gsm_authen.c b/tests/msc_vlr/msc_vlr_test_gsm_authen.c
index 46dd9a1..f6f1ab6 100644
--- a/tests/msc_vlr/msc_vlr_test_gsm_authen.c
+++ b/tests/msc_vlr/msc_vlr_test_gsm_authen.c
@@ -573,9 +573,15 @@
 	EXPECT_ACCEPTED(false);
 	thwart_rx_non_initial_requests();
 
-	btw("MS replies with an Identity Response");
-	expect_bssap_clear();
+	btw("MS replies with an Identity Response, VLR sends the IMEI to HLR");
+	gsup_expect_tx("30010809710000004026f050090824433224433224f0");
 	ms_sends_msg("0559084a32244332244302");
+	EXPECT_ACCEPTED(false);
+	thwart_rx_non_initial_requests();
+
+	btw("HLR accepts the IMEI");
+	expect_bssap_clear();
+	gsup_rx("32010809710000004026f0510100", NULL);
 	VERBOSE_ASSERT(bssap_clear_sent, == true, "%d");
 
 	btw("LU was successful, and the conn has already been closed");
@@ -600,6 +606,192 @@
 	comment_end();
 }
 
+static void test_gsm_authen_imei_nack()
+{
+	struct vlr_subscr *vsub;
+	const char *imsi = "901700000004620";
+
+	comment_start();
+
+	net->authentication_required = true;
+	net->vlr->cfg.check_imei_rqd = true;
+
+	btw("Location Update request causes a GSUP Send Auth Info request to HLR");
+	lu_result_sent = RES_NONE;
+	gsup_expect_tx("08010809710000004026f0");
+	ms_sends_msg("0508020081680001"
+		     "30" /* <-- Revision Level == 1, i.e. is_r99 == false */
+		     "089910070000006402");
+	OSMO_ASSERT(gsup_tx_confirmed);
+	VERBOSE_ASSERT(lu_result_sent, == RES_NONE, "%d");
+
+	btw("from HLR, rx _SEND_AUTH_INFO_RESULT; VLR sends Auth Req to MS");
+	auth_request_sent = false;
+	auth_request_expect_rand = "585df1ae287f6e273dce07090d61320b";
+	auth_request_expect_autn = NULL;
+	/* Based on a Ki of 000102030405060708090a0b0c0d0e0f */
+	gsup_rx("0a"
+		/* imsi */
+		"0108" "09710000004026f0"
+		/* 5 auth vectors... */
+		/* TL    TL     rand */
+		"0322"  "2010" "585df1ae287f6e273dce07090d61320b"
+		/*       TL     sres       TL     kc */
+			"2104" "2d8b2c3e" "2208" "61855fb81fc2a800"
+		"0322"  "2010" "12aca96fb4ffdea5c985cbafa9b6e18b"
+			"2104" "20bde240" "2208" "07fa7502e07e1c00"
+		"0322"  "2010" "e7c03ba7cf0e2fde82b2dc4d63077d42"
+			"2104" "a29514ae" "2208" "e2b234f807886400"
+		"0322"  "2010" "fa8f20b781b5881329d4fea26b1a3c51"
+			"2104" "5afc8d72" "2208" "2392f14f709ae000"
+		"0322"  "2010" "0fd4cc8dbe8715d1f439e304edfd68dc"
+			"2104" "bc8d1c5b" "2208" "da7cdd6bfe2d7000",
+		NULL);
+	VERBOSE_ASSERT(auth_request_sent, == true, "%d");
+	VERBOSE_ASSERT(lu_result_sent, == RES_NONE, "%d");
+
+	btw("If the HLR were to send a GSUP _UPDATE_LOCATION_RESULT we'd still reject");
+	gsup_rx("06010809710000004026f0", NULL);
+	EXPECT_ACCEPTED(false);
+
+	thwart_rx_non_initial_requests();
+
+	VERBOSE_ASSERT(lu_result_sent, == RES_NONE, "%d");
+
+	btw("MS sends Authen Response, VLR accepts and sends GSUP LU Req to HLR");
+	gsup_expect_tx("04010809710000004026f0280102");
+	ms_sends_msg("05542d8b2c3e");
+	VERBOSE_ASSERT(lu_result_sent, == RES_NONE, "%d");
+
+	btw("HLR sends _INSERT_DATA_REQUEST, VLR responds with _INSERT_DATA_RESULT");
+	gsup_rx("10010809710000004026f00804036470f1",
+		"12010809710000004026f0");
+	VERBOSE_ASSERT(lu_result_sent, == RES_NONE, "%d");
+
+	btw("HLR also sends GSUP _UPDATE_LOCATION_RESULT, and we send an ID Request for the IMEI to the MS");
+	dtap_expect_tx("051802");
+	gsup_rx("06010809710000004026f0", NULL);
+
+	btw("We will only do business when the IMEI is known");
+	EXPECT_CONN_COUNT(1);
+	vsub = vlr_subscr_find_by_imsi(net->vlr, imsi);
+	OSMO_ASSERT(vsub);
+	VERBOSE_ASSERT(vsub->imei[0], == 0, "%d");
+	vlr_subscr_put(vsub);
+	EXPECT_ACCEPTED(false);
+	thwart_rx_non_initial_requests();
+
+	btw("MS replies with an Identity Response, VLR sends the IMEI to HLR");
+	gsup_expect_tx("30010809710000004026f050090824433224433224f0");
+	ms_sends_msg("0559084a32244332244302");
+	EXPECT_ACCEPTED(false);
+	thwart_rx_non_initial_requests();
+
+	expect_bssap_clear();
+	btw("HLR does not like the IMEI and sends NACK");
+	gsup_rx("32010809710000004026f0510101", NULL);
+	EXPECT_ACCEPTED(false);
+	thwart_rx_non_initial_requests();
+
+	bss_sends_clear_complete();
+	EXPECT_CONN_COUNT(0);
+	clear_vlr();
+	comment_end();
+}
+
+static void test_gsm_authen_imei_err()
+{
+	struct vlr_subscr *vsub;
+	const char *imsi = "901700000004620";
+
+	comment_start();
+
+	net->authentication_required = true;
+	net->vlr->cfg.check_imei_rqd = true;
+
+	btw("Location Update request causes a GSUP Send Auth Info request to HLR");
+	lu_result_sent = RES_NONE;
+	gsup_expect_tx("08010809710000004026f0");
+	ms_sends_msg("0508020081680001"
+		     "30" /* <-- Revision Level == 1, i.e. is_r99 == false */
+		     "089910070000006402");
+	OSMO_ASSERT(gsup_tx_confirmed);
+	VERBOSE_ASSERT(lu_result_sent, == RES_NONE, "%d");
+
+	btw("from HLR, rx _SEND_AUTH_INFO_RESULT; VLR sends Auth Req to MS");
+	auth_request_sent = false;
+	auth_request_expect_rand = "585df1ae287f6e273dce07090d61320b";
+	auth_request_expect_autn = NULL;
+	/* Based on a Ki of 000102030405060708090a0b0c0d0e0f */
+	gsup_rx("0a"
+		/* imsi */
+		"0108" "09710000004026f0"
+		/* 5 auth vectors... */
+		/* TL    TL     rand */
+		"0322"  "2010" "585df1ae287f6e273dce07090d61320b"
+		/*       TL     sres       TL     kc */
+			"2104" "2d8b2c3e" "2208" "61855fb81fc2a800"
+		"0322"  "2010" "12aca96fb4ffdea5c985cbafa9b6e18b"
+			"2104" "20bde240" "2208" "07fa7502e07e1c00"
+		"0322"  "2010" "e7c03ba7cf0e2fde82b2dc4d63077d42"
+			"2104" "a29514ae" "2208" "e2b234f807886400"
+		"0322"  "2010" "fa8f20b781b5881329d4fea26b1a3c51"
+			"2104" "5afc8d72" "2208" "2392f14f709ae000"
+		"0322"  "2010" "0fd4cc8dbe8715d1f439e304edfd68dc"
+			"2104" "bc8d1c5b" "2208" "da7cdd6bfe2d7000",
+		NULL);
+	VERBOSE_ASSERT(auth_request_sent, == true, "%d");
+	VERBOSE_ASSERT(lu_result_sent, == RES_NONE, "%d");
+
+	btw("If the HLR were to send a GSUP _UPDATE_LOCATION_RESULT we'd still reject");
+	gsup_rx("06010809710000004026f0", NULL);
+	EXPECT_ACCEPTED(false);
+
+	thwart_rx_non_initial_requests();
+
+	VERBOSE_ASSERT(lu_result_sent, == RES_NONE, "%d");
+
+	btw("MS sends Authen Response, VLR accepts and sends GSUP LU Req to HLR");
+	gsup_expect_tx("04010809710000004026f0280102");
+	ms_sends_msg("05542d8b2c3e");
+	VERBOSE_ASSERT(lu_result_sent, == RES_NONE, "%d");
+
+	btw("HLR sends _INSERT_DATA_REQUEST, VLR responds with _INSERT_DATA_RESULT");
+	gsup_rx("10010809710000004026f00804036470f1",
+		"12010809710000004026f0");
+	VERBOSE_ASSERT(lu_result_sent, == RES_NONE, "%d");
+
+	btw("HLR also sends GSUP _UPDATE_LOCATION_RESULT, and we send an ID Request for the IMEI to the MS");
+	dtap_expect_tx("051802");
+	gsup_rx("06010809710000004026f0", NULL);
+
+	btw("We will only do business when the IMEI is known");
+	EXPECT_CONN_COUNT(1);
+	vsub = vlr_subscr_find_by_imsi(net->vlr, imsi);
+	OSMO_ASSERT(vsub);
+	VERBOSE_ASSERT(vsub->imei[0], == 0, "%d");
+	vlr_subscr_put(vsub);
+	EXPECT_ACCEPTED(false);
+	thwart_rx_non_initial_requests();
+
+	btw("MS replies with an Identity Response, VLR sends the IMEI to HLR");
+	gsup_expect_tx("30010809710000004026f050090824433224433224f0");
+	ms_sends_msg("0559084a32244332244302");
+	EXPECT_ACCEPTED(false);
+	thwart_rx_non_initial_requests();
+
+	expect_bssap_clear();
+	btw("HLR can't parse the message and returns ERR");
+	gsup_rx("31010809710000004026f0020160", NULL);
+	EXPECT_ACCEPTED(false);
+	thwart_rx_non_initial_requests();
+
+	bss_sends_clear_complete();
+	EXPECT_CONN_COUNT(0);
+	clear_vlr();
+	comment_end();
+}
+
 static void test_gsm_authen_tmsi_imei()
 {
 	struct vlr_subscr *vsub;
@@ -676,8 +868,14 @@
 	EXPECT_ACCEPTED(false);
 	thwart_rx_non_initial_requests();
 
-	btw("MS replies with an Identity Response");
+	btw("MS replies with an Identity Response, VLR sends the IMEI to HLR");
+	gsup_expect_tx("30010809710000004026f050090824433224433224f0");
 	ms_sends_msg("0559084a32244332244302");
+	EXPECT_ACCEPTED(false);
+	thwart_rx_non_initial_requests();
+
+	btw("HLR accepts the IMEI");
+	gsup_rx("32010809710000004026f0510100", NULL);
 
 	btw("a LU Accept with a new TMSI was sent, waiting for TMSI Realloc Compl");
 	EXPECT_CONN_COUNT(1);
@@ -998,6 +1196,8 @@
 	test_gsm_authen,
 	test_gsm_authen_tmsi,
 	test_gsm_authen_imei,
+	test_gsm_authen_imei_nack,
+	test_gsm_authen_imei_err,
 	test_gsm_authen_tmsi_imei,
 	test_gsm_milenage_authen,
 	test_wrong_sres_length,
diff --git a/tests/msc_vlr/msc_vlr_test_gsm_authen.err b/tests/msc_vlr/msc_vlr_test_gsm_authen.err
index fddfe07..c69fde8 100644
--- a/tests/msc_vlr/msc_vlr_test_gsm_authen.err
+++ b/tests/msc_vlr/msc_vlr_test_gsm_authen.err
@@ -1254,16 +1254,36 @@
 DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: GSM48_MT_RR_SYSINFO_1
 DRLL Dispatching 04.08 message SMS:0x01 (0x9:0x1)
 DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: SMS:0x01
-- MS replies with an Identity Response
+- MS replies with an Identity Response, VLR sends the IMEI to HLR
   MSC <--GERAN-A-- MS: GSM48_MT_MM_ID_RESP
 DREF IMSI-901700000004620:MSISDN-46071: MSC conn use + dtap == 1 (0x2: dtap)
 DRLL Dispatching 04.08 message GSM48_MT_MM_ID_RESP (0x5:0x19)
 DMM IDENTITY RESPONSE: MI=IMEI-423423423423420
 DVLR set IMEI on subscriber; IMSI=901700000004620 IMEI=423423423423420
 DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_WAIT_LU_COMPL}: Received Event VLR_ULA_E_ID_IMEI
+DVLR GSUP tx: 30010809710000004026f050090824433224433224f0
+GSUP --> HLR: OSMO_GSUP_MSGT_CHECK_IMEI_REQUEST: 30010809710000004026f050090824433224433224f0
+DREF IMSI-901700000004620:MSISDN-46071: MSC conn use - dtap == 0 (0x0: )
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Received Event RAN_CONN_E_UNUSED
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Awaiting results for Auth+Ciph, overruling event RAN_CONN_E_UNUSED
+ran_conn_is_accepted() == false
+  requests shall be thwarted
+DRLL Dispatching 04.08 message GSM48_MT_CC_SETUP (0x3:0x5)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: GSM48_MT_CC_SETUP
+DRLL Dispatching 04.08 message unknown 0x33 (0x5:0x33)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: unknown 0x33
+DRLL Dispatching 04.08 message GSM48_MT_RR_SYSINFO_1 (0x6:0x19)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: GSM48_MT_RR_SYSINFO_1
+DRLL Dispatching 04.08 message SMS:0x01 (0x9:0x1)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: SMS:0x01
+- HLR accepts the IMEI
+<-- GSUP rx OSMO_GSUP_MSGT_CHECK_IMEI_RESULT: 32010809710000004026f0510100
+DVLR GSUP rx 14: 32010809710000004026f0510100
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage increases to: 2
+DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_WAIT_LU_COMPL}: Received Event VLR_ULA_E_HLR_IMEI_ACK
 DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_WAIT_IMEI}: Received Event LU_COMPL_VLR_E_IMEI_CHECK_ACK
 - sending LU Accept for IMSI-901700000004620:MSISDN-46071
-DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage increases to: 2
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage increases to: 3
 DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_WAIT_IMEI}: state_chg to LU_COMPL_VLR_S_DONE
 DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_WAIT_LU_COMPL}: Received Event VLR_ULA_E_LU_COMPL_SUCCESS
 DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_DONE}: Terminating (cause = OSMO_FSM_TERM_PARENT)
@@ -1275,11 +1295,12 @@
 DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: state_chg to RAN_CONN_S_ACCEPTED
 DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_ACCEPTED}: Received Event RAN_CONN_E_UNUSED
 DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_ACCEPTED}: state_chg to RAN_CONN_S_RELEASING
-DREF IMSI-901700000004620:MSISDN-46071: MSC conn use + release == 2 (0x102: dtap,release)
-DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage increases to: 3
-DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage decreases to: 2
+DREF IMSI-901700000004620:MSISDN-46071: MSC conn use + release == 1 (0x100: release)
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage increases to: 4
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage decreases to: 3
 - BSSAP Clear --GERAN-A--> MS
-DREF IMSI-901700000004620:MSISDN-46071: MSC conn use - dtap == 1 (0x100: release)
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage decreases to: 2
+<-- GSUP rx OSMO_GSUP_MSGT_CHECK_IMEI_RESULT: vlr_gsupc_read_cb() returns 0
   bssap_clear_sent == 1
 - LU was successful, and the conn has already been closed
   lu_result_sent == 1
@@ -1337,6 +1358,455 @@
 full talloc report on 'msgb' (total      0 bytes in   1 blocks)
 talloc_total_blocks(tall_bsc_ctx) == 13
 
+===== test_gsm_authen_imei_nack
+- Location Update request causes a GSUP Send Auth Info request to HLR
+  MSC <--GERAN-A-- MS: GSM48_MT_MM_LOC_UPD_REQUEST
+  new conn
+DMM RAN_conn{RAN_CONN_S_NEW}: Allocated
+DREF unknown: MSC conn use + compl_l3 == 1 (0x1: compl_l3)
+DRLL Dispatching 04.08 message GSM48_MT_MM_LOC_UPD_REQUEST (0x5:0x8)
+DMM RAN_conn(IMSI-901700000004620:GERAN-A-0:LU){RAN_CONN_S_NEW}: Updated ID
+DMM RAN_conn(IMSI-901700000004620:GERAN-A-0:LU){RAN_CONN_S_NEW}: LOCATION UPDATING REQUEST: MI=IMSI-901700000004620 LU-type=IMSI-ATTACH
+DMM RAN_conn(IMSI-901700000004620:GERAN-A-0:LU){RAN_CONN_S_NEW}: LU/new-LAC: 1/23
+DVLR vlr_lu_fsm(IMSI-901700000004620:GERAN-A-0:LU){VLR_ULA_S_IDLE}: Allocated
+DVLR vlr_lu_fsm(IMSI-901700000004620:GERAN-A-0:LU){VLR_ULA_S_IDLE}: is child of RAN_conn(IMSI-901700000004620:GERAN-A-0:LU)
+DVLR vlr_lu_fsm(IMSI-901700000004620:GERAN-A-0:LU){VLR_ULA_S_IDLE}: rev=GSM net=GERAN Auth (no Ciph)
+DVLR vlr_lu_fsm(IMSI-901700000004620:GERAN-A-0:LU){VLR_ULA_S_IDLE}: Received Event VLR_ULA_E_UPDATE_LA
+DREF VLR subscr unknown usage increases to: 1
+DVLR set IMSI on subscriber; IMSI=901700000004620 id=901700000004620
+DVLR New subscr, IMSI: 901700000004620
+DREF VLR subscr IMSI-901700000004620 usage increases to: 2
+DMM RAN_conn(IMSI-901700000004620:GERAN-A-0:LU){RAN_CONN_S_NEW}: Updated ID
+DREF VLR subscr IMSI-901700000004620 usage decreases to: 1
+DVLR vlr_lu_fsm(IMSI-901700000004620:GERAN-A-0:LU){VLR_ULA_S_IDLE}: vlr_loc_upd_node1()
+DVLR vlr_lu_fsm(IMSI-901700000004620:GERAN-A-0:LU){VLR_ULA_S_IDLE}: state_chg to VLR_ULA_S_WAIT_AUTH
+DVLR VLR_Authenticate(IMSI-901700000004620:GERAN-A-0:LU){VLR_SUB_AS_NEEDS_AUTH}: Allocated
+DVLR VLR_Authenticate(IMSI-901700000004620:GERAN-A-0:LU){VLR_SUB_AS_NEEDS_AUTH}: is child of vlr_lu_fsm(IMSI-901700000004620:GERAN-A-0:LU)
+DVLR VLR_Authenticate(IMSI-901700000004620:GERAN-A-0:LU){VLR_SUB_AS_NEEDS_AUTH}: Received Event VLR_AUTH_E_START
+DVLR GSUP tx: 08010809710000004026f0
+GSUP --> HLR: OSMO_GSUP_MSGT_SEND_AUTH_INFO_REQUEST: 08010809710000004026f0
+DVLR VLR_Authenticate(IMSI-901700000004620:GERAN-A-0:LU){VLR_SUB_AS_NEEDS_AUTH}: state_chg to VLR_SUB_AS_NEEDS_AUTH_WAIT_AI
+DMM RAN_conn(IMSI-901700000004620:GERAN-A-0:LU){RAN_CONN_S_NEW}: Received Event RAN_CONN_E_COMPLETE_LAYER_3
+DMM RAN_conn(IMSI-901700000004620:GERAN-A-0:LU){RAN_CONN_S_NEW}: state_chg to RAN_CONN_S_AUTH_CIPH
+DREF IMSI-901700000004620: MSC conn use - compl_l3 == 0 (0x0: )
+DMM RAN_conn(IMSI-901700000004620:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Received Event RAN_CONN_E_UNUSED
+DMM RAN_conn(IMSI-901700000004620:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Awaiting results for Auth+Ciph, overruling event RAN_CONN_E_UNUSED
+  lu_result_sent == 0
+- from HLR, rx _SEND_AUTH_INFO_RESULT; VLR sends Auth Req to MS
+<-- GSUP rx OSMO_GSUP_MSGT_SEND_AUTH_INFO_RESULT: 0a010809710000004026f003222010585df1ae287f6e273dce07090d61320b21042d8b2c3e220861855fb81fc2a8000322201012aca96fb4ffdea5c985cbafa9b6e18b210420bde240220807fa7502e07e1c0003222010e7c03ba7cf0e2fde82b2dc4d63077d422104a29514ae2208e2b234f80788640003222010fa8f20b781b5881329d4fea26b1a3c5121045afc8d7222082392f14f709ae000032220100fd4cc8dbe8715d1f439e304edfd68dc2104bc8d1c5b2208da7cdd6bfe2d7000
+DVLR GSUP rx 191: 0a010809710000004026f003222010585df1ae287f6e273dce07090d61320b21042d8b2c3e220861855fb81fc2a8000322201012aca96fb4ffdea5c985cbafa9b6e18b210420bde240220807fa7502e07e1c0003222010e7c03ba7cf0e2fde82b2dc4d63077d422104a29514ae2208e2b234f80788640003222010fa8f20b781b5881329d4fea26b1a3c5121045afc8d7222082392f14f709ae000032220100fd4cc8dbe8715d1f439e304edfd68dc2104bc8d1c5b2208da7cdd6bfe2d7000
+DREF VLR subscr IMSI-901700000004620 usage increases to: 2
+DVLR VLR_Authenticate(IMSI-901700000004620:GERAN-A-0:LU){VLR_SUB_AS_NEEDS_AUTH_WAIT_AI}: Received Event VLR_AUTH_E_HLR_SAI_ACK
+DVLR SUBSCR(IMSI-901700000004620) Received 5 auth tuples
+DVLR VLR_Authenticate(IMSI-901700000004620:GERAN-A-0:LU){VLR_SUB_AS_NEEDS_AUTH_WAIT_AI}: state_chg to VLR_SUB_AS_WAIT_RESP
+DVLR VLR_Authenticate(IMSI-901700000004620:GERAN-A-0:LU){VLR_SUB_AS_WAIT_RESP}: got auth tuple: use_count=1 key_seq=0 -- will use GSM AKA (is_r99=no, at->vec.auth_types=0x1)
+- sending GSM Auth Request for IMSI-901700000004620: tuple use_count=1 key_seq=0 auth_types=0x1 and...
+- ...rand=585df1ae287f6e273dce07090d61320b
+- ...expecting sres=2d8b2c3e
+DREF VLR subscr IMSI-901700000004620 usage decreases to: 1
+<-- GSUP rx OSMO_GSUP_MSGT_SEND_AUTH_INFO_RESULT: vlr_gsupc_read_cb() returns 0
+  auth_request_sent == 1
+  lu_result_sent == 0
+- If the HLR were to send a GSUP _UPDATE_LOCATION_RESULT we'd still reject
+<-- GSUP rx OSMO_GSUP_MSGT_UPDATE_LOCATION_RESULT: 06010809710000004026f0
+DVLR GSUP rx 11: 06010809710000004026f0
+DREF VLR subscr IMSI-901700000004620 usage increases to: 2
+DVLR vlr_lu_fsm(IMSI-901700000004620:GERAN-A-0:LU){VLR_ULA_S_WAIT_AUTH}: Received Event VLR_ULA_E_HLR_LU_RES
+DVLR vlr_lu_fsm(IMSI-901700000004620:GERAN-A-0:LU){VLR_ULA_S_WAIT_AUTH}: Event VLR_ULA_E_HLR_LU_RES not permitted
+DREF VLR subscr IMSI-901700000004620 usage decreases to: 1
+<-- GSUP rx OSMO_GSUP_MSGT_UPDATE_LOCATION_RESULT: vlr_gsupc_read_cb() returns 0
+ran_conn_is_accepted() == false
+  requests shall be thwarted
+DRLL Dispatching 04.08 message GSM48_MT_CC_SETUP (0x3:0x5)
+DRLL subscr IMSI-901700000004620: Message not permitted for initial conn: GSM48_MT_CC_SETUP
+DRLL Dispatching 04.08 message unknown 0x33 (0x5:0x33)
+DRLL subscr IMSI-901700000004620: Message not permitted for initial conn: unknown 0x33
+DRLL Dispatching 04.08 message GSM48_MT_RR_SYSINFO_1 (0x6:0x19)
+DRLL subscr IMSI-901700000004620: Message not permitted for initial conn: GSM48_MT_RR_SYSINFO_1
+DRLL Dispatching 04.08 message SMS:0x01 (0x9:0x1)
+DRLL subscr IMSI-901700000004620: Message not permitted for initial conn: SMS:0x01
+  lu_result_sent == 0
+- MS sends Authen Response, VLR accepts and sends GSUP LU Req to HLR
+  MSC <--GERAN-A-- MS: GSM48_MT_MM_AUTH_RESP
+DREF IMSI-901700000004620: MSC conn use + dtap == 1 (0x2: dtap)
+DRLL Dispatching 04.08 message GSM48_MT_MM_AUTH_RESP (0x5:0x14)
+DMM IMSI-901700000004620: MM GSM AUTHENTICATION RESPONSE (sres = 2d8b2c3e)
+DVLR VLR_Authenticate(IMSI-901700000004620:GERAN-A-0:LU){VLR_SUB_AS_WAIT_RESP}: Received Event VLR_AUTH_E_MS_AUTH_RESP
+DVLR SUBSCR(IMSI-901700000004620) AUTH on GERAN received SRES/RES: 2d8b2c3e (4 bytes)
+DVLR SUBSCR(IMSI-901700000004620) AUTH established GSM security context
+DVLR VLR_Authenticate(IMSI-901700000004620:GERAN-A-0:LU){VLR_SUB_AS_WAIT_RESP}: Authentication terminating with result PASSED
+DVLR VLR_Authenticate(IMSI-901700000004620:GERAN-A-0:LU){VLR_SUB_AS_WAIT_RESP}: state_chg to VLR_SUB_AS_AUTHENTICATED
+DVLR VLR_Authenticate(IMSI-901700000004620:GERAN-A-0:LU){VLR_SUB_AS_AUTHENTICATED}: Terminating (cause = OSMO_FSM_TERM_REGULAR)
+DVLR VLR_Authenticate(IMSI-901700000004620:GERAN-A-0:LU){VLR_SUB_AS_AUTHENTICATED}: Removing from parent vlr_lu_fsm(IMSI-901700000004620:GERAN-A-0:LU)
+DVLR VLR_Authenticate(IMSI-901700000004620:GERAN-A-0:LU){VLR_SUB_AS_AUTHENTICATED}: Freeing instance
+DVLR VLR_Authenticate(IMSI-901700000004620:GERAN-A-0:LU){VLR_SUB_AS_AUTHENTICATED}: Deallocated
+DVLR vlr_lu_fsm(IMSI-901700000004620:GERAN-A-0:LU){VLR_ULA_S_WAIT_AUTH}: Received Event VLR_ULA_E_AUTH_RES
+DVLR vlr_lu_fsm(IMSI-901700000004620:GERAN-A-0:LU){VLR_ULA_S_WAIT_AUTH}: vlr_loc_upd_post_auth()
+DVLR vlr_lu_fsm(IMSI-901700000004620:GERAN-A-0:LU){VLR_ULA_S_WAIT_AUTH}: vlr_loc_upd_post_ciph()
+DVLR vlr_lu_fsm(IMSI-901700000004620:GERAN-A-0:LU){VLR_ULA_S_WAIT_AUTH}: vlr_loc_upd_node_4()
+DVLR vlr_lu_fsm(IMSI-901700000004620:GERAN-A-0:LU){VLR_ULA_S_WAIT_AUTH}: state_chg to VLR_ULA_S_WAIT_HLR_UPD
+DVLR upd_hlr_vlr_fsm(IMSI-901700000004620:GERAN-A-0:LU){UPD_HLR_VLR_S_INIT}: Allocated
+DVLR upd_hlr_vlr_fsm(IMSI-901700000004620:GERAN-A-0:LU){UPD_HLR_VLR_S_INIT}: is child of vlr_lu_fsm(IMSI-901700000004620:GERAN-A-0:LU)
+DVLR upd_hlr_vlr_fsm(IMSI-901700000004620:GERAN-A-0:LU){UPD_HLR_VLR_S_INIT}: Received Event UPD_HLR_VLR_E_START
+DVLR GSUP tx: 04010809710000004026f0280102
+GSUP --> HLR: OSMO_GSUP_MSGT_UPDATE_LOCATION_REQUEST: 04010809710000004026f0280102
+DVLR upd_hlr_vlr_fsm(IMSI-901700000004620:GERAN-A-0:LU){UPD_HLR_VLR_S_INIT}: state_chg to UPD_HLR_VLR_S_WAIT_FOR_DATA
+DREF IMSI-901700000004620: MSC conn use - dtap == 0 (0x0: )
+DMM RAN_conn(IMSI-901700000004620:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Received Event RAN_CONN_E_UNUSED
+DMM RAN_conn(IMSI-901700000004620:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Awaiting results for Auth+Ciph, overruling event RAN_CONN_E_UNUSED
+  lu_result_sent == 0
+- HLR sends _INSERT_DATA_REQUEST, VLR responds with _INSERT_DATA_RESULT
+<-- GSUP rx OSMO_GSUP_MSGT_INSERT_DATA_REQUEST: 10010809710000004026f00804036470f1
+DVLR GSUP rx 17: 10010809710000004026f00804036470f1
+DREF VLR subscr IMSI-901700000004620 usage increases to: 2
+DVLR IMSI:901700000004620 has MSISDN:46071
+DVLR SUBSCR(IMSI-901700000004620:MSISDN-46071) VLR: update for IMSI=901700000004620 (MSISDN=46071, used=2)
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Updated ID
+DVLR GSUP tx: 12010809710000004026f0
+GSUP --> HLR: OSMO_GSUP_MSGT_INSERT_DATA_RESULT: 12010809710000004026f0
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage decreases to: 1
+<-- GSUP rx OSMO_GSUP_MSGT_INSERT_DATA_REQUEST: vlr_gsupc_read_cb() returns 0
+  lu_result_sent == 0
+- HLR also sends GSUP _UPDATE_LOCATION_RESULT, and we send an ID Request for the IMEI to the MS
+<-- GSUP rx OSMO_GSUP_MSGT_UPDATE_LOCATION_RESULT: 06010809710000004026f0
+DVLR GSUP rx 11: 06010809710000004026f0
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage increases to: 2
+DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_WAIT_HLR_UPD}: Received Event VLR_ULA_E_HLR_LU_RES
+DVLR upd_hlr_vlr_fsm(IMSI-901700000004620:GERAN-A-0:LU){UPD_HLR_VLR_S_WAIT_FOR_DATA}: Received Event UPD_HLR_VLR_E_UPD_LOC_ACK
+DVLR upd_hlr_vlr_fsm(IMSI-901700000004620:GERAN-A-0:LU){UPD_HLR_VLR_S_WAIT_FOR_DATA}: state_chg to UPD_HLR_VLR_S_DONE
+DVLR upd_hlr_vlr_fsm(IMSI-901700000004620:GERAN-A-0:LU){UPD_HLR_VLR_S_DONE}: Terminating (cause = OSMO_FSM_TERM_REGULAR)
+DVLR upd_hlr_vlr_fsm(IMSI-901700000004620:GERAN-A-0:LU){UPD_HLR_VLR_S_DONE}: Removing from parent vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU)
+DVLR upd_hlr_vlr_fsm(IMSI-901700000004620:GERAN-A-0:LU){UPD_HLR_VLR_S_DONE}: Freeing instance
+DVLR upd_hlr_vlr_fsm(IMSI-901700000004620:GERAN-A-0:LU){UPD_HLR_VLR_S_DONE}: Deallocated
+DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_WAIT_HLR_UPD}: Received Event VLR_ULA_E_UPD_HLR_COMPL
+DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_WAIT_HLR_UPD}: state_chg to VLR_ULA_S_WAIT_LU_COMPL
+DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_INIT}: Allocated
+DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_INIT}: is child of vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU)
+DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_INIT}: Received Event LU_COMPL_VLR_E_START
+DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_INIT}: state_chg to LU_COMPL_VLR_S_WAIT_SUB_PRES
+DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_WAIT_SUB_PRES}: Received Event LU_COMPL_VLR_E_SUB_PRES_COMPL
+DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_WAIT_SUB_PRES}: state_chg to LU_COMPL_VLR_S_WAIT_IMEI
+DMSC msc_tx 3 bytes to IMSI-901700000004620:MSISDN-46071 via GERAN-A
+- DTAP --GERAN-A--> MS: GSM48_MT_MM_ID_REQ: 051802
+- DTAP matches expected message
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage decreases to: 1
+<-- GSUP rx OSMO_GSUP_MSGT_UPDATE_LOCATION_RESULT: vlr_gsupc_read_cb() returns 0
+- We will only do business when the IMEI is known
+  llist_count(&net->ran_conns) == 1
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage increases to: 2
+  vsub->imei[0] == 0
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage decreases to: 1
+ran_conn_is_accepted() == false
+  requests shall be thwarted
+DRLL Dispatching 04.08 message GSM48_MT_CC_SETUP (0x3:0x5)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: GSM48_MT_CC_SETUP
+DRLL Dispatching 04.08 message unknown 0x33 (0x5:0x33)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: unknown 0x33
+DRLL Dispatching 04.08 message GSM48_MT_RR_SYSINFO_1 (0x6:0x19)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: GSM48_MT_RR_SYSINFO_1
+DRLL Dispatching 04.08 message SMS:0x01 (0x9:0x1)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: SMS:0x01
+- MS replies with an Identity Response, VLR sends the IMEI to HLR
+  MSC <--GERAN-A-- MS: GSM48_MT_MM_ID_RESP
+DREF IMSI-901700000004620:MSISDN-46071: MSC conn use + dtap == 1 (0x2: dtap)
+DRLL Dispatching 04.08 message GSM48_MT_MM_ID_RESP (0x5:0x19)
+DMM IDENTITY RESPONSE: MI=IMEI-423423423423420
+DVLR set IMEI on subscriber; IMSI=901700000004620 IMEI=423423423423420
+DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_WAIT_LU_COMPL}: Received Event VLR_ULA_E_ID_IMEI
+DVLR GSUP tx: 30010809710000004026f050090824433224433224f0
+GSUP --> HLR: OSMO_GSUP_MSGT_CHECK_IMEI_REQUEST: 30010809710000004026f050090824433224433224f0
+DREF IMSI-901700000004620:MSISDN-46071: MSC conn use - dtap == 0 (0x0: )
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Received Event RAN_CONN_E_UNUSED
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Awaiting results for Auth+Ciph, overruling event RAN_CONN_E_UNUSED
+ran_conn_is_accepted() == false
+  requests shall be thwarted
+DRLL Dispatching 04.08 message GSM48_MT_CC_SETUP (0x3:0x5)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: GSM48_MT_CC_SETUP
+DRLL Dispatching 04.08 message unknown 0x33 (0x5:0x33)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: unknown 0x33
+DRLL Dispatching 04.08 message GSM48_MT_RR_SYSINFO_1 (0x6:0x19)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: GSM48_MT_RR_SYSINFO_1
+DRLL Dispatching 04.08 message SMS:0x01 (0x9:0x1)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: SMS:0x01
+- HLR does not like the IMEI and sends NACK
+<-- GSUP rx OSMO_GSUP_MSGT_CHECK_IMEI_RESULT: 32010809710000004026f0510101
+DVLR GSUP rx 14: 32010809710000004026f0510101
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage increases to: 2
+DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_WAIT_LU_COMPL}: Received Event VLR_ULA_E_HLR_IMEI_NACK
+DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_WAIT_IMEI}: Received Event LU_COMPL_VLR_E_IMEI_CHECK_NACK
+- sending LU Reject for IMSI-901700000004620:MSISDN-46071, cause 6
+DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_WAIT_IMEI}: state_chg to LU_COMPL_VLR_S_DONE
+DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_WAIT_LU_COMPL}: Received Event VLR_ULA_E_LU_COMPL_FAILURE
+DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_DONE}: Terminating (cause = OSMO_FSM_TERM_PARENT)
+DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_DONE}: Removing from parent vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU)
+DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_DONE}: Freeing instance
+DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_DONE}: Deallocated
+- sending LU Reject for IMSI-901700000004620:MSISDN-46071, cause 6
+DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_WAIT_LU_COMPL}: state_chg to VLR_ULA_S_DONE
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Received Event RAN_CONN_E_CN_CLOSE
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: state_chg to RAN_CONN_S_RELEASING
+DREF IMSI-901700000004620:MSISDN-46071: MSC conn use + release == 1 (0x100: release)
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage increases to: 3
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage decreases to: 2
+- BSSAP Clear --GERAN-A--> MS
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage decreases to: 1
+<-- GSUP rx OSMO_GSUP_MSGT_CHECK_IMEI_RESULT: vlr_gsupc_read_cb() returns 0
+ran_conn_is_accepted() == false
+  requests shall be thwarted
+DRLL Dispatching 04.08 message GSM48_MT_CC_SETUP (0x3:0x5)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: GSM48_MT_CC_SETUP
+DRLL Dispatching 04.08 message unknown 0x33 (0x5:0x33)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: unknown 0x33
+DRLL Dispatching 04.08 message GSM48_MT_RR_SYSINFO_1 (0x6:0x19)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: GSM48_MT_RR_SYSINFO_1
+DRLL Dispatching 04.08 message SMS:0x01 (0x9:0x1)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: SMS:0x01
+- BSS sends BSSMAP Clear Complete
+DREF IMSI-901700000004620:MSISDN-46071: MSC conn use - release == 0 (0x0: )
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_RELEASING}: Received Event RAN_CONN_E_UNUSED
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_RELEASING}: state_chg to RAN_CONN_S_RELEASED
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_RELEASED}: Terminating (cause = OSMO_FSM_TERM_REGULAR)
+DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_DONE}: Terminating (cause = OSMO_FSM_TERM_PARENT)
+DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_DONE}: Removing from parent RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU)
+DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_DONE}: fsm_lu_cleanup called with cause OSMO_FSM_TERM_PARENT
+DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_DONE}: Freeing instance
+DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_DONE}: Deallocated
+DRLL IMSI-901700000004620:MSISDN-46071: Freeing RAN connection
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage decreases to: 0
+DREF freeing VLR subscr IMSI-901700000004620:MSISDN-46071
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_RELEASED}: Freeing instance
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_RELEASED}: Deallocated
+  llist_count(&net->ran_conns) == 0
+===== test_gsm_authen_imei_nack: SUCCESS
+
+full talloc report on 'msgb' (total      0 bytes in   1 blocks)
+talloc_total_blocks(tall_bsc_ctx) == 13
+
+===== test_gsm_authen_imei_err
+- Location Update request causes a GSUP Send Auth Info request to HLR
+  MSC <--GERAN-A-- MS: GSM48_MT_MM_LOC_UPD_REQUEST
+  new conn
+DMM RAN_conn{RAN_CONN_S_NEW}: Allocated
+DREF unknown: MSC conn use + compl_l3 == 1 (0x1: compl_l3)
+DRLL Dispatching 04.08 message GSM48_MT_MM_LOC_UPD_REQUEST (0x5:0x8)
+DMM RAN_conn(IMSI-901700000004620:GERAN-A-0:LU){RAN_CONN_S_NEW}: Updated ID
+DMM RAN_conn(IMSI-901700000004620:GERAN-A-0:LU){RAN_CONN_S_NEW}: LOCATION UPDATING REQUEST: MI=IMSI-901700000004620 LU-type=IMSI-ATTACH
+DMM RAN_conn(IMSI-901700000004620:GERAN-A-0:LU){RAN_CONN_S_NEW}: LU/new-LAC: 1/23
+DVLR vlr_lu_fsm(IMSI-901700000004620:GERAN-A-0:LU){VLR_ULA_S_IDLE}: Allocated
+DVLR vlr_lu_fsm(IMSI-901700000004620:GERAN-A-0:LU){VLR_ULA_S_IDLE}: is child of RAN_conn(IMSI-901700000004620:GERAN-A-0:LU)
+DVLR vlr_lu_fsm(IMSI-901700000004620:GERAN-A-0:LU){VLR_ULA_S_IDLE}: rev=GSM net=GERAN Auth (no Ciph)
+DVLR vlr_lu_fsm(IMSI-901700000004620:GERAN-A-0:LU){VLR_ULA_S_IDLE}: Received Event VLR_ULA_E_UPDATE_LA
+DREF VLR subscr unknown usage increases to: 1
+DVLR set IMSI on subscriber; IMSI=901700000004620 id=901700000004620
+DVLR New subscr, IMSI: 901700000004620
+DREF VLR subscr IMSI-901700000004620 usage increases to: 2
+DMM RAN_conn(IMSI-901700000004620:GERAN-A-0:LU){RAN_CONN_S_NEW}: Updated ID
+DREF VLR subscr IMSI-901700000004620 usage decreases to: 1
+DVLR vlr_lu_fsm(IMSI-901700000004620:GERAN-A-0:LU){VLR_ULA_S_IDLE}: vlr_loc_upd_node1()
+DVLR vlr_lu_fsm(IMSI-901700000004620:GERAN-A-0:LU){VLR_ULA_S_IDLE}: state_chg to VLR_ULA_S_WAIT_AUTH
+DVLR VLR_Authenticate(IMSI-901700000004620:GERAN-A-0:LU){VLR_SUB_AS_NEEDS_AUTH}: Allocated
+DVLR VLR_Authenticate(IMSI-901700000004620:GERAN-A-0:LU){VLR_SUB_AS_NEEDS_AUTH}: is child of vlr_lu_fsm(IMSI-901700000004620:GERAN-A-0:LU)
+DVLR VLR_Authenticate(IMSI-901700000004620:GERAN-A-0:LU){VLR_SUB_AS_NEEDS_AUTH}: Received Event VLR_AUTH_E_START
+DVLR GSUP tx: 08010809710000004026f0
+GSUP --> HLR: OSMO_GSUP_MSGT_SEND_AUTH_INFO_REQUEST: 08010809710000004026f0
+DVLR VLR_Authenticate(IMSI-901700000004620:GERAN-A-0:LU){VLR_SUB_AS_NEEDS_AUTH}: state_chg to VLR_SUB_AS_NEEDS_AUTH_WAIT_AI
+DMM RAN_conn(IMSI-901700000004620:GERAN-A-0:LU){RAN_CONN_S_NEW}: Received Event RAN_CONN_E_COMPLETE_LAYER_3
+DMM RAN_conn(IMSI-901700000004620:GERAN-A-0:LU){RAN_CONN_S_NEW}: state_chg to RAN_CONN_S_AUTH_CIPH
+DREF IMSI-901700000004620: MSC conn use - compl_l3 == 0 (0x0: )
+DMM RAN_conn(IMSI-901700000004620:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Received Event RAN_CONN_E_UNUSED
+DMM RAN_conn(IMSI-901700000004620:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Awaiting results for Auth+Ciph, overruling event RAN_CONN_E_UNUSED
+  lu_result_sent == 0
+- from HLR, rx _SEND_AUTH_INFO_RESULT; VLR sends Auth Req to MS
+<-- GSUP rx OSMO_GSUP_MSGT_SEND_AUTH_INFO_RESULT: 0a010809710000004026f003222010585df1ae287f6e273dce07090d61320b21042d8b2c3e220861855fb81fc2a8000322201012aca96fb4ffdea5c985cbafa9b6e18b210420bde240220807fa7502e07e1c0003222010e7c03ba7cf0e2fde82b2dc4d63077d422104a29514ae2208e2b234f80788640003222010fa8f20b781b5881329d4fea26b1a3c5121045afc8d7222082392f14f709ae000032220100fd4cc8dbe8715d1f439e304edfd68dc2104bc8d1c5b2208da7cdd6bfe2d7000
+DVLR GSUP rx 191: 0a010809710000004026f003222010585df1ae287f6e273dce07090d61320b21042d8b2c3e220861855fb81fc2a8000322201012aca96fb4ffdea5c985cbafa9b6e18b210420bde240220807fa7502e07e1c0003222010e7c03ba7cf0e2fde82b2dc4d63077d422104a29514ae2208e2b234f80788640003222010fa8f20b781b5881329d4fea26b1a3c5121045afc8d7222082392f14f709ae000032220100fd4cc8dbe8715d1f439e304edfd68dc2104bc8d1c5b2208da7cdd6bfe2d7000
+DREF VLR subscr IMSI-901700000004620 usage increases to: 2
+DVLR VLR_Authenticate(IMSI-901700000004620:GERAN-A-0:LU){VLR_SUB_AS_NEEDS_AUTH_WAIT_AI}: Received Event VLR_AUTH_E_HLR_SAI_ACK
+DVLR SUBSCR(IMSI-901700000004620) Received 5 auth tuples
+DVLR VLR_Authenticate(IMSI-901700000004620:GERAN-A-0:LU){VLR_SUB_AS_NEEDS_AUTH_WAIT_AI}: state_chg to VLR_SUB_AS_WAIT_RESP
+DVLR VLR_Authenticate(IMSI-901700000004620:GERAN-A-0:LU){VLR_SUB_AS_WAIT_RESP}: got auth tuple: use_count=1 key_seq=0 -- will use GSM AKA (is_r99=no, at->vec.auth_types=0x1)
+- sending GSM Auth Request for IMSI-901700000004620: tuple use_count=1 key_seq=0 auth_types=0x1 and...
+- ...rand=585df1ae287f6e273dce07090d61320b
+- ...expecting sres=2d8b2c3e
+DREF VLR subscr IMSI-901700000004620 usage decreases to: 1
+<-- GSUP rx OSMO_GSUP_MSGT_SEND_AUTH_INFO_RESULT: vlr_gsupc_read_cb() returns 0
+  auth_request_sent == 1
+  lu_result_sent == 0
+- If the HLR were to send a GSUP _UPDATE_LOCATION_RESULT we'd still reject
+<-- GSUP rx OSMO_GSUP_MSGT_UPDATE_LOCATION_RESULT: 06010809710000004026f0
+DVLR GSUP rx 11: 06010809710000004026f0
+DREF VLR subscr IMSI-901700000004620 usage increases to: 2
+DVLR vlr_lu_fsm(IMSI-901700000004620:GERAN-A-0:LU){VLR_ULA_S_WAIT_AUTH}: Received Event VLR_ULA_E_HLR_LU_RES
+DVLR vlr_lu_fsm(IMSI-901700000004620:GERAN-A-0:LU){VLR_ULA_S_WAIT_AUTH}: Event VLR_ULA_E_HLR_LU_RES not permitted
+DREF VLR subscr IMSI-901700000004620 usage decreases to: 1
+<-- GSUP rx OSMO_GSUP_MSGT_UPDATE_LOCATION_RESULT: vlr_gsupc_read_cb() returns 0
+ran_conn_is_accepted() == false
+  requests shall be thwarted
+DRLL Dispatching 04.08 message GSM48_MT_CC_SETUP (0x3:0x5)
+DRLL subscr IMSI-901700000004620: Message not permitted for initial conn: GSM48_MT_CC_SETUP
+DRLL Dispatching 04.08 message unknown 0x33 (0x5:0x33)
+DRLL subscr IMSI-901700000004620: Message not permitted for initial conn: unknown 0x33
+DRLL Dispatching 04.08 message GSM48_MT_RR_SYSINFO_1 (0x6:0x19)
+DRLL subscr IMSI-901700000004620: Message not permitted for initial conn: GSM48_MT_RR_SYSINFO_1
+DRLL Dispatching 04.08 message SMS:0x01 (0x9:0x1)
+DRLL subscr IMSI-901700000004620: Message not permitted for initial conn: SMS:0x01
+  lu_result_sent == 0
+- MS sends Authen Response, VLR accepts and sends GSUP LU Req to HLR
+  MSC <--GERAN-A-- MS: GSM48_MT_MM_AUTH_RESP
+DREF IMSI-901700000004620: MSC conn use + dtap == 1 (0x2: dtap)
+DRLL Dispatching 04.08 message GSM48_MT_MM_AUTH_RESP (0x5:0x14)
+DMM IMSI-901700000004620: MM GSM AUTHENTICATION RESPONSE (sres = 2d8b2c3e)
+DVLR VLR_Authenticate(IMSI-901700000004620:GERAN-A-0:LU){VLR_SUB_AS_WAIT_RESP}: Received Event VLR_AUTH_E_MS_AUTH_RESP
+DVLR SUBSCR(IMSI-901700000004620) AUTH on GERAN received SRES/RES: 2d8b2c3e (4 bytes)
+DVLR SUBSCR(IMSI-901700000004620) AUTH established GSM security context
+DVLR VLR_Authenticate(IMSI-901700000004620:GERAN-A-0:LU){VLR_SUB_AS_WAIT_RESP}: Authentication terminating with result PASSED
+DVLR VLR_Authenticate(IMSI-901700000004620:GERAN-A-0:LU){VLR_SUB_AS_WAIT_RESP}: state_chg to VLR_SUB_AS_AUTHENTICATED
+DVLR VLR_Authenticate(IMSI-901700000004620:GERAN-A-0:LU){VLR_SUB_AS_AUTHENTICATED}: Terminating (cause = OSMO_FSM_TERM_REGULAR)
+DVLR VLR_Authenticate(IMSI-901700000004620:GERAN-A-0:LU){VLR_SUB_AS_AUTHENTICATED}: Removing from parent vlr_lu_fsm(IMSI-901700000004620:GERAN-A-0:LU)
+DVLR VLR_Authenticate(IMSI-901700000004620:GERAN-A-0:LU){VLR_SUB_AS_AUTHENTICATED}: Freeing instance
+DVLR VLR_Authenticate(IMSI-901700000004620:GERAN-A-0:LU){VLR_SUB_AS_AUTHENTICATED}: Deallocated
+DVLR vlr_lu_fsm(IMSI-901700000004620:GERAN-A-0:LU){VLR_ULA_S_WAIT_AUTH}: Received Event VLR_ULA_E_AUTH_RES
+DVLR vlr_lu_fsm(IMSI-901700000004620:GERAN-A-0:LU){VLR_ULA_S_WAIT_AUTH}: vlr_loc_upd_post_auth()
+DVLR vlr_lu_fsm(IMSI-901700000004620:GERAN-A-0:LU){VLR_ULA_S_WAIT_AUTH}: vlr_loc_upd_post_ciph()
+DVLR vlr_lu_fsm(IMSI-901700000004620:GERAN-A-0:LU){VLR_ULA_S_WAIT_AUTH}: vlr_loc_upd_node_4()
+DVLR vlr_lu_fsm(IMSI-901700000004620:GERAN-A-0:LU){VLR_ULA_S_WAIT_AUTH}: state_chg to VLR_ULA_S_WAIT_HLR_UPD
+DVLR upd_hlr_vlr_fsm(IMSI-901700000004620:GERAN-A-0:LU){UPD_HLR_VLR_S_INIT}: Allocated
+DVLR upd_hlr_vlr_fsm(IMSI-901700000004620:GERAN-A-0:LU){UPD_HLR_VLR_S_INIT}: is child of vlr_lu_fsm(IMSI-901700000004620:GERAN-A-0:LU)
+DVLR upd_hlr_vlr_fsm(IMSI-901700000004620:GERAN-A-0:LU){UPD_HLR_VLR_S_INIT}: Received Event UPD_HLR_VLR_E_START
+DVLR GSUP tx: 04010809710000004026f0280102
+GSUP --> HLR: OSMO_GSUP_MSGT_UPDATE_LOCATION_REQUEST: 04010809710000004026f0280102
+DVLR upd_hlr_vlr_fsm(IMSI-901700000004620:GERAN-A-0:LU){UPD_HLR_VLR_S_INIT}: state_chg to UPD_HLR_VLR_S_WAIT_FOR_DATA
+DREF IMSI-901700000004620: MSC conn use - dtap == 0 (0x0: )
+DMM RAN_conn(IMSI-901700000004620:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Received Event RAN_CONN_E_UNUSED
+DMM RAN_conn(IMSI-901700000004620:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Awaiting results for Auth+Ciph, overruling event RAN_CONN_E_UNUSED
+  lu_result_sent == 0
+- HLR sends _INSERT_DATA_REQUEST, VLR responds with _INSERT_DATA_RESULT
+<-- GSUP rx OSMO_GSUP_MSGT_INSERT_DATA_REQUEST: 10010809710000004026f00804036470f1
+DVLR GSUP rx 17: 10010809710000004026f00804036470f1
+DREF VLR subscr IMSI-901700000004620 usage increases to: 2
+DVLR IMSI:901700000004620 has MSISDN:46071
+DVLR SUBSCR(IMSI-901700000004620:MSISDN-46071) VLR: update for IMSI=901700000004620 (MSISDN=46071, used=2)
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Updated ID
+DVLR GSUP tx: 12010809710000004026f0
+GSUP --> HLR: OSMO_GSUP_MSGT_INSERT_DATA_RESULT: 12010809710000004026f0
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage decreases to: 1
+<-- GSUP rx OSMO_GSUP_MSGT_INSERT_DATA_REQUEST: vlr_gsupc_read_cb() returns 0
+  lu_result_sent == 0
+- HLR also sends GSUP _UPDATE_LOCATION_RESULT, and we send an ID Request for the IMEI to the MS
+<-- GSUP rx OSMO_GSUP_MSGT_UPDATE_LOCATION_RESULT: 06010809710000004026f0
+DVLR GSUP rx 11: 06010809710000004026f0
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage increases to: 2
+DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_WAIT_HLR_UPD}: Received Event VLR_ULA_E_HLR_LU_RES
+DVLR upd_hlr_vlr_fsm(IMSI-901700000004620:GERAN-A-0:LU){UPD_HLR_VLR_S_WAIT_FOR_DATA}: Received Event UPD_HLR_VLR_E_UPD_LOC_ACK
+DVLR upd_hlr_vlr_fsm(IMSI-901700000004620:GERAN-A-0:LU){UPD_HLR_VLR_S_WAIT_FOR_DATA}: state_chg to UPD_HLR_VLR_S_DONE
+DVLR upd_hlr_vlr_fsm(IMSI-901700000004620:GERAN-A-0:LU){UPD_HLR_VLR_S_DONE}: Terminating (cause = OSMO_FSM_TERM_REGULAR)
+DVLR upd_hlr_vlr_fsm(IMSI-901700000004620:GERAN-A-0:LU){UPD_HLR_VLR_S_DONE}: Removing from parent vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU)
+DVLR upd_hlr_vlr_fsm(IMSI-901700000004620:GERAN-A-0:LU){UPD_HLR_VLR_S_DONE}: Freeing instance
+DVLR upd_hlr_vlr_fsm(IMSI-901700000004620:GERAN-A-0:LU){UPD_HLR_VLR_S_DONE}: Deallocated
+DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_WAIT_HLR_UPD}: Received Event VLR_ULA_E_UPD_HLR_COMPL
+DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_WAIT_HLR_UPD}: state_chg to VLR_ULA_S_WAIT_LU_COMPL
+DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_INIT}: Allocated
+DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_INIT}: is child of vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU)
+DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_INIT}: Received Event LU_COMPL_VLR_E_START
+DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_INIT}: state_chg to LU_COMPL_VLR_S_WAIT_SUB_PRES
+DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_WAIT_SUB_PRES}: Received Event LU_COMPL_VLR_E_SUB_PRES_COMPL
+DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_WAIT_SUB_PRES}: state_chg to LU_COMPL_VLR_S_WAIT_IMEI
+DMSC msc_tx 3 bytes to IMSI-901700000004620:MSISDN-46071 via GERAN-A
+- DTAP --GERAN-A--> MS: GSM48_MT_MM_ID_REQ: 051802
+- DTAP matches expected message
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage decreases to: 1
+<-- GSUP rx OSMO_GSUP_MSGT_UPDATE_LOCATION_RESULT: vlr_gsupc_read_cb() returns 0
+- We will only do business when the IMEI is known
+  llist_count(&net->ran_conns) == 1
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage increases to: 2
+  vsub->imei[0] == 0
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage decreases to: 1
+ran_conn_is_accepted() == false
+  requests shall be thwarted
+DRLL Dispatching 04.08 message GSM48_MT_CC_SETUP (0x3:0x5)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: GSM48_MT_CC_SETUP
+DRLL Dispatching 04.08 message unknown 0x33 (0x5:0x33)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: unknown 0x33
+DRLL Dispatching 04.08 message GSM48_MT_RR_SYSINFO_1 (0x6:0x19)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: GSM48_MT_RR_SYSINFO_1
+DRLL Dispatching 04.08 message SMS:0x01 (0x9:0x1)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: SMS:0x01
+- MS replies with an Identity Response, VLR sends the IMEI to HLR
+  MSC <--GERAN-A-- MS: GSM48_MT_MM_ID_RESP
+DREF IMSI-901700000004620:MSISDN-46071: MSC conn use + dtap == 1 (0x2: dtap)
+DRLL Dispatching 04.08 message GSM48_MT_MM_ID_RESP (0x5:0x19)
+DMM IDENTITY RESPONSE: MI=IMEI-423423423423420
+DVLR set IMEI on subscriber; IMSI=901700000004620 IMEI=423423423423420
+DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_WAIT_LU_COMPL}: Received Event VLR_ULA_E_ID_IMEI
+DVLR GSUP tx: 30010809710000004026f050090824433224433224f0
+GSUP --> HLR: OSMO_GSUP_MSGT_CHECK_IMEI_REQUEST: 30010809710000004026f050090824433224433224f0
+DREF IMSI-901700000004620:MSISDN-46071: MSC conn use - dtap == 0 (0x0: )
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Received Event RAN_CONN_E_UNUSED
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Awaiting results for Auth+Ciph, overruling event RAN_CONN_E_UNUSED
+ran_conn_is_accepted() == false
+  requests shall be thwarted
+DRLL Dispatching 04.08 message GSM48_MT_CC_SETUP (0x3:0x5)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: GSM48_MT_CC_SETUP
+DRLL Dispatching 04.08 message unknown 0x33 (0x5:0x33)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: unknown 0x33
+DRLL Dispatching 04.08 message GSM48_MT_RR_SYSINFO_1 (0x6:0x19)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: GSM48_MT_RR_SYSINFO_1
+DRLL Dispatching 04.08 message SMS:0x01 (0x9:0x1)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: SMS:0x01
+- HLR can't parse the message and returns ERR
+<-- GSUP rx OSMO_GSUP_MSGT_CHECK_IMEI_ERROR: 31010809710000004026f0020160
+DVLR GSUP rx 14: 31010809710000004026f0020160
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage increases to: 2
+DVLR SUBSCR(IMSI-901700000004620:MSISDN-46071) Check_IMEI_VLR failed; gmm_cause: Invalid mandatory information
+DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_WAIT_LU_COMPL}: Received Event VLR_ULA_E_HLR_IMEI_NACK
+DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_WAIT_IMEI}: Received Event LU_COMPL_VLR_E_IMEI_CHECK_NACK
+- sending LU Reject for IMSI-901700000004620:MSISDN-46071, cause 6
+DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_WAIT_IMEI}: state_chg to LU_COMPL_VLR_S_DONE
+DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_WAIT_LU_COMPL}: Received Event VLR_ULA_E_LU_COMPL_FAILURE
+DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_DONE}: Terminating (cause = OSMO_FSM_TERM_PARENT)
+DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_DONE}: Removing from parent vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU)
+DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_DONE}: Freeing instance
+DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_DONE}: Deallocated
+- sending LU Reject for IMSI-901700000004620:MSISDN-46071, cause 6
+DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_WAIT_LU_COMPL}: state_chg to VLR_ULA_S_DONE
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Received Event RAN_CONN_E_CN_CLOSE
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: state_chg to RAN_CONN_S_RELEASING
+DREF IMSI-901700000004620:MSISDN-46071: MSC conn use + release == 1 (0x100: release)
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage increases to: 3
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage decreases to: 2
+- BSSAP Clear --GERAN-A--> MS
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage decreases to: 1
+<-- GSUP rx OSMO_GSUP_MSGT_CHECK_IMEI_ERROR: vlr_gsupc_read_cb() returns 0
+ran_conn_is_accepted() == false
+  requests shall be thwarted
+DRLL Dispatching 04.08 message GSM48_MT_CC_SETUP (0x3:0x5)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: GSM48_MT_CC_SETUP
+DRLL Dispatching 04.08 message unknown 0x33 (0x5:0x33)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: unknown 0x33
+DRLL Dispatching 04.08 message GSM48_MT_RR_SYSINFO_1 (0x6:0x19)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: GSM48_MT_RR_SYSINFO_1
+DRLL Dispatching 04.08 message SMS:0x01 (0x9:0x1)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: SMS:0x01
+- BSS sends BSSMAP Clear Complete
+DREF IMSI-901700000004620:MSISDN-46071: MSC conn use - release == 0 (0x0: )
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_RELEASING}: Received Event RAN_CONN_E_UNUSED
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_RELEASING}: state_chg to RAN_CONN_S_RELEASED
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_RELEASED}: Terminating (cause = OSMO_FSM_TERM_REGULAR)
+DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_DONE}: Terminating (cause = OSMO_FSM_TERM_PARENT)
+DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_DONE}: Removing from parent RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU)
+DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_DONE}: fsm_lu_cleanup called with cause OSMO_FSM_TERM_PARENT
+DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_DONE}: Freeing instance
+DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_DONE}: Deallocated
+DRLL IMSI-901700000004620:MSISDN-46071: Freeing RAN connection
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage decreases to: 0
+DREF freeing VLR subscr IMSI-901700000004620:MSISDN-46071
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_RELEASED}: Freeing instance
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_RELEASED}: Deallocated
+  llist_count(&net->ran_conns) == 0
+===== test_gsm_authen_imei_err: SUCCESS
+
+full talloc report on 'msgb' (total      0 bytes in   1 blocks)
+talloc_total_blocks(tall_bsc_ctx) == 13
+
 ===== test_gsm_authen_tmsi_imei
 - Location Update request causes a GSUP Send Auth Info request to HLR
   MSC <--GERAN-A-- MS: GSM48_MT_MM_LOC_UPD_REQUEST
@@ -1485,22 +1955,41 @@
 DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: GSM48_MT_RR_SYSINFO_1
 DRLL Dispatching 04.08 message SMS:0x01 (0x9:0x1)
 DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: SMS:0x01
-- MS replies with an Identity Response
+- MS replies with an Identity Response, VLR sends the IMEI to HLR
   MSC <--GERAN-A-- MS: GSM48_MT_MM_ID_RESP
 DREF IMSI-901700000004620:MSISDN-46071: MSC conn use + dtap == 1 (0x2: dtap)
 DRLL Dispatching 04.08 message GSM48_MT_MM_ID_RESP (0x5:0x19)
 DMM IDENTITY RESPONSE: MI=IMEI-423423423423420
 DVLR set IMEI on subscriber; IMSI=901700000004620 IMEI=423423423423420
 DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_WAIT_LU_COMPL}: Received Event VLR_ULA_E_ID_IMEI
+DVLR GSUP tx: 30010809710000004026f050090824433224433224f0
+GSUP --> HLR: OSMO_GSUP_MSGT_CHECK_IMEI_REQUEST: 30010809710000004026f050090824433224433224f0
+DREF IMSI-901700000004620:MSISDN-46071: MSC conn use - dtap == 0 (0x0: )
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Received Event RAN_CONN_E_UNUSED
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Awaiting results for Auth+Ciph, overruling event RAN_CONN_E_UNUSED
+ran_conn_is_accepted() == false
+  requests shall be thwarted
+DRLL Dispatching 04.08 message GSM48_MT_CC_SETUP (0x3:0x5)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: GSM48_MT_CC_SETUP
+DRLL Dispatching 04.08 message unknown 0x33 (0x5:0x33)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: unknown 0x33
+DRLL Dispatching 04.08 message GSM48_MT_RR_SYSINFO_1 (0x6:0x19)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: GSM48_MT_RR_SYSINFO_1
+DRLL Dispatching 04.08 message SMS:0x01 (0x9:0x1)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: SMS:0x01
+- HLR accepts the IMEI
+<-- GSUP rx OSMO_GSUP_MSGT_CHECK_IMEI_RESULT: 32010809710000004026f0510100
+DVLR GSUP rx 14: 32010809710000004026f0510100
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage increases to: 2
+DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_WAIT_LU_COMPL}: Received Event VLR_ULA_E_HLR_IMEI_ACK
 DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_WAIT_IMEI_TMSI}: Received Event LU_COMPL_VLR_E_IMEI_CHECK_ACK
 DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_WAIT_IMEI_TMSI}: lu_compl_vlr_new_tmsi()
-DVLR SUBSCR(IMSI-901700000004620:MSISDN-46071:TMSInew-0x03020100) VLR: update for IMSI=901700000004620 (MSISDN=46071, used=1)
+DVLR SUBSCR(IMSI-901700000004620:MSISDN-46071:TMSInew-0x03020100) VLR: update for IMSI=901700000004620 (MSISDN=46071, used=2)
 DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:TMSInew-0x03020100:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Updated ID
 DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_WAIT_IMEI_TMSI}: state_chg to LU_COMPL_VLR_S_WAIT_TMSI_CNF
 - sending LU Accept for IMSI-901700000004620:MSISDN-46071:TMSInew-0x03020100, with TMSI 0x03020100
-DREF IMSI-901700000004620:MSISDN-46071:TMSInew-0x03020100: MSC conn use - dtap == 0 (0x0: )
-DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:TMSInew-0x03020100:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Received Event RAN_CONN_E_UNUSED
-DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:TMSInew-0x03020100:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Awaiting results for Auth+Ciph, overruling event RAN_CONN_E_UNUSED
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071:TMSInew-0x03020100 usage decreases to: 1
+<-- GSUP rx OSMO_GSUP_MSGT_CHECK_IMEI_RESULT: vlr_gsupc_read_cb() returns 0
 - a LU Accept with a new TMSI was sent, waiting for TMSI Realloc Compl
   llist_count(&net->ran_conns) == 1
   lu_result_sent == 1
diff --git a/tests/msc_vlr/msc_vlr_test_gsm_ciph.c b/tests/msc_vlr/msc_vlr_test_gsm_ciph.c
index a641ec2..31b5f5d 100644
--- a/tests/msc_vlr/msc_vlr_test_gsm_ciph.c
+++ b/tests/msc_vlr/msc_vlr_test_gsm_ciph.c
@@ -553,9 +553,15 @@
 	EXPECT_ACCEPTED(false);
 	thwart_rx_non_initial_requests();
 
-	btw("MS replies with an Identity Response");
-	expect_bssap_clear();
+	btw("MS replies with an Identity Response, VLR sends the IMEI to HLR");
+	gsup_expect_tx("30010809710000004026f050090824433224433224f0");
 	ms_sends_msg("0559084a32244332244302");
+	EXPECT_ACCEPTED(false);
+	thwart_rx_non_initial_requests();
+
+	btw("HLR accepts the IMEI");
+	expect_bssap_clear();
+	gsup_rx("32010809710000004026f0510100", NULL);
 	VERBOSE_ASSERT(bssap_clear_sent, == true, "%d");
 
 	btw("LU was successful, and the conn has already been closed");
@@ -758,8 +764,14 @@
 	EXPECT_ACCEPTED(false);
 	thwart_rx_non_initial_requests();
 
-	btw("MS replies with an Identity Response");
+	btw("MS replies with an Identity Response, VLR sends the IMEI to HLR");
+	gsup_expect_tx("30010809710000004026f050090824433224433224f0");
 	ms_sends_msg("0559084a32244332244302");
+	EXPECT_ACCEPTED(false);
+	thwart_rx_non_initial_requests();
+
+	btw("HLR accepts the IMEI");
+	gsup_rx("32010809710000004026f0510100", NULL);
 
 	btw("a LU Accept with a new TMSI was sent, waiting for TMSI Realloc Compl");
 	EXPECT_CONN_COUNT(1);
diff --git a/tests/msc_vlr/msc_vlr_test_gsm_ciph.err b/tests/msc_vlr/msc_vlr_test_gsm_ciph.err
index 65e182c..914683f 100644
--- a/tests/msc_vlr/msc_vlr_test_gsm_ciph.err
+++ b/tests/msc_vlr/msc_vlr_test_gsm_ciph.err
@@ -1192,16 +1192,36 @@
 DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: GSM48_MT_RR_SYSINFO_1
 DRLL Dispatching 04.08 message SMS:0x01 (0x9:0x1)
 DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: SMS:0x01
-- MS replies with an Identity Response
+- MS replies with an Identity Response, VLR sends the IMEI to HLR
   MSC <--GERAN-A-- MS: GSM48_MT_MM_ID_RESP
 DREF IMSI-901700000004620:MSISDN-46071: MSC conn use + dtap == 1 (0x2: dtap)
 DRLL Dispatching 04.08 message GSM48_MT_MM_ID_RESP (0x5:0x19)
 DMM IDENTITY RESPONSE: MI=IMEI-423423423423420
 DVLR set IMEI on subscriber; IMSI=901700000004620 IMEI=423423423423420
 DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_WAIT_LU_COMPL}: Received Event VLR_ULA_E_ID_IMEI
+DVLR GSUP tx: 30010809710000004026f050090824433224433224f0
+GSUP --> HLR: OSMO_GSUP_MSGT_CHECK_IMEI_REQUEST: 30010809710000004026f050090824433224433224f0
+DREF IMSI-901700000004620:MSISDN-46071: MSC conn use - dtap == 0 (0x0: )
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Received Event RAN_CONN_E_UNUSED
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Awaiting results for Auth+Ciph, overruling event RAN_CONN_E_UNUSED
+ran_conn_is_accepted() == false
+  requests shall be thwarted
+DRLL Dispatching 04.08 message GSM48_MT_CC_SETUP (0x3:0x5)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: GSM48_MT_CC_SETUP
+DRLL Dispatching 04.08 message unknown 0x33 (0x5:0x33)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: unknown 0x33
+DRLL Dispatching 04.08 message GSM48_MT_RR_SYSINFO_1 (0x6:0x19)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: GSM48_MT_RR_SYSINFO_1
+DRLL Dispatching 04.08 message SMS:0x01 (0x9:0x1)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: SMS:0x01
+- HLR accepts the IMEI
+<-- GSUP rx OSMO_GSUP_MSGT_CHECK_IMEI_RESULT: 32010809710000004026f0510100
+DVLR GSUP rx 14: 32010809710000004026f0510100
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage increases to: 2
+DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_WAIT_LU_COMPL}: Received Event VLR_ULA_E_HLR_IMEI_ACK
 DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_WAIT_IMEI}: Received Event LU_COMPL_VLR_E_IMEI_CHECK_ACK
 - sending LU Accept for IMSI-901700000004620:MSISDN-46071
-DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage increases to: 2
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage increases to: 3
 DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_WAIT_IMEI}: state_chg to LU_COMPL_VLR_S_DONE
 DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_WAIT_LU_COMPL}: Received Event VLR_ULA_E_LU_COMPL_SUCCESS
 DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_DONE}: Terminating (cause = OSMO_FSM_TERM_PARENT)
@@ -1213,11 +1233,12 @@
 DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: state_chg to RAN_CONN_S_ACCEPTED
 DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_ACCEPTED}: Received Event RAN_CONN_E_UNUSED
 DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_ACCEPTED}: state_chg to RAN_CONN_S_RELEASING
-DREF IMSI-901700000004620:MSISDN-46071: MSC conn use + release == 2 (0x102: dtap,release)
-DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage increases to: 3
-DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage decreases to: 2
+DREF IMSI-901700000004620:MSISDN-46071: MSC conn use + release == 1 (0x100: release)
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage increases to: 4
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage decreases to: 3
 - BSSAP Clear --GERAN-A--> MS
-DREF IMSI-901700000004620:MSISDN-46071: MSC conn use - dtap == 1 (0x100: release)
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage decreases to: 2
+<-- GSUP rx OSMO_GSUP_MSGT_CHECK_IMEI_RESULT: vlr_gsupc_read_cb() returns 0
   bssap_clear_sent == 1
 - LU was successful, and the conn has already been closed
   lu_result_sent == 1
@@ -1651,22 +1672,41 @@
 DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: GSM48_MT_RR_SYSINFO_1
 DRLL Dispatching 04.08 message SMS:0x01 (0x9:0x1)
 DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: SMS:0x01
-- MS replies with an Identity Response
+- MS replies with an Identity Response, VLR sends the IMEI to HLR
   MSC <--GERAN-A-- MS: GSM48_MT_MM_ID_RESP
 DREF IMSI-901700000004620:MSISDN-46071: MSC conn use + dtap == 1 (0x2: dtap)
 DRLL Dispatching 04.08 message GSM48_MT_MM_ID_RESP (0x5:0x19)
 DMM IDENTITY RESPONSE: MI=IMEI-423423423423420
 DVLR set IMEI on subscriber; IMSI=901700000004620 IMEI=423423423423420
 DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_WAIT_LU_COMPL}: Received Event VLR_ULA_E_ID_IMEI
+DVLR GSUP tx: 30010809710000004026f050090824433224433224f0
+GSUP --> HLR: OSMO_GSUP_MSGT_CHECK_IMEI_REQUEST: 30010809710000004026f050090824433224433224f0
+DREF IMSI-901700000004620:MSISDN-46071: MSC conn use - dtap == 0 (0x0: )
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Received Event RAN_CONN_E_UNUSED
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Awaiting results for Auth+Ciph, overruling event RAN_CONN_E_UNUSED
+ran_conn_is_accepted() == false
+  requests shall be thwarted
+DRLL Dispatching 04.08 message GSM48_MT_CC_SETUP (0x3:0x5)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: GSM48_MT_CC_SETUP
+DRLL Dispatching 04.08 message unknown 0x33 (0x5:0x33)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: unknown 0x33
+DRLL Dispatching 04.08 message GSM48_MT_RR_SYSINFO_1 (0x6:0x19)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: GSM48_MT_RR_SYSINFO_1
+DRLL Dispatching 04.08 message SMS:0x01 (0x9:0x1)
+DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: SMS:0x01
+- HLR accepts the IMEI
+<-- GSUP rx OSMO_GSUP_MSGT_CHECK_IMEI_RESULT: 32010809710000004026f0510100
+DVLR GSUP rx 14: 32010809710000004026f0510100
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage increases to: 2
+DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_WAIT_LU_COMPL}: Received Event VLR_ULA_E_HLR_IMEI_ACK
 DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_WAIT_IMEI_TMSI}: Received Event LU_COMPL_VLR_E_IMEI_CHECK_ACK
 DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_WAIT_IMEI_TMSI}: lu_compl_vlr_new_tmsi()
-DVLR SUBSCR(IMSI-901700000004620:MSISDN-46071:TMSInew-0x03020100) VLR: update for IMSI=901700000004620 (MSISDN=46071, used=1)
+DVLR SUBSCR(IMSI-901700000004620:MSISDN-46071:TMSInew-0x03020100) VLR: update for IMSI=901700000004620 (MSISDN=46071, used=2)
 DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:TMSInew-0x03020100:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Updated ID
 DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_WAIT_IMEI_TMSI}: state_chg to LU_COMPL_VLR_S_WAIT_TMSI_CNF
 - sending LU Accept for IMSI-901700000004620:MSISDN-46071:TMSInew-0x03020100, with TMSI 0x03020100
-DREF IMSI-901700000004620:MSISDN-46071:TMSInew-0x03020100: MSC conn use - dtap == 0 (0x0: )
-DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:TMSInew-0x03020100:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Received Event RAN_CONN_E_UNUSED
-DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:TMSInew-0x03020100:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Awaiting results for Auth+Ciph, overruling event RAN_CONN_E_UNUSED
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071:TMSInew-0x03020100 usage decreases to: 1
+<-- GSUP rx OSMO_GSUP_MSGT_CHECK_IMEI_RESULT: vlr_gsupc_read_cb() returns 0
 - a LU Accept with a new TMSI was sent, waiting for TMSI Realloc Compl
   llist_count(&net->ran_conns) == 1
   lu_result_sent == 1
diff --git a/tests/msc_vlr/msc_vlr_test_no_authen.c b/tests/msc_vlr/msc_vlr_test_no_authen.c
index 3162149..d52d3d6 100644
--- a/tests/msc_vlr/msc_vlr_test_no_authen.c
+++ b/tests/msc_vlr/msc_vlr_test_no_authen.c
@@ -428,11 +428,15 @@
 	EXPECT_ACCEPTED(false);
 	thwart_rx_non_initial_requests();
 
-	btw("MS replies with an Identity Response");
-	expect_bssap_clear();
+	btw("MS replies with an Identity Response, VLR sends the IMEI to HLR");
+	gsup_expect_tx("30010809710000004026f050090824433224433224f0");
 	/* 3GPP TS 23.003: 6.2.1 Composition of IMEI: the IMEI ends with a
 	 * spare digit that shall be sent as zero by the MS. */
 	ms_sends_msg("0559084a32244332244302");
+
+	btw("HLR accepts the IMEI");
+	expect_bssap_clear();
+	gsup_rx("32010809710000004026f0510100", NULL);
 	VERBOSE_ASSERT(bssap_clear_sent, == true, "%d");
 
 	btw("LU was successful, and the conn has already been closed");
@@ -499,9 +503,13 @@
 	EXPECT_ACCEPTED(false);
 	thwart_rx_non_initial_requests();
 
-	btw("MS replies with an Identity Response");
+	btw("MS replies with an Identity Response, VLR sends the IMEI to HLR");
+	gsup_expect_tx("30010809710000004026f050090824433224433224f0");
 	ms_sends_msg("0559084a32244332244302");
 
+	btw("HLR accepts the IMEI");
+	gsup_rx("32010809710000004026f0510100", NULL);
+
 	btw("a LU Accept with a new TMSI was sent, waiting for TMSI Realloc Compl");
 	EXPECT_CONN_COUNT(1);
 	VERBOSE_ASSERT(lu_result_sent, == RES_ACCEPT, "%d");
@@ -652,9 +660,13 @@
 	EXPECT_ACCEPTED(false);
 	thwart_rx_non_initial_requests();
 
-	btw("MS replies with an Identity Response");
-	expect_bssap_clear();
+	btw("MS replies with an Identity Response, VLR sends the IMEI to HLR");
+	gsup_expect_tx("30010809710000004026f050090824433224433224f0");
 	ms_sends_msg("0559084a32244332244302");
+
+	btw("HLR accepts the IMEI");
+	expect_bssap_clear();
+	gsup_rx("32010809710000004026f0510100", NULL);
 	VERBOSE_ASSERT(bssap_clear_sent, == true, "%d");
 
 	btw("LU was successful, and the conn has already been closed");
@@ -874,9 +886,13 @@
 	EXPECT_ACCEPTED(false);
 	thwart_rx_non_initial_requests();
 
-	btw("MS replies with an Identity Response");
+	btw("MS replies with an Identity Response, VLR sends the IMEI to HLR");
+	gsup_expect_tx("30010809710000004026f050090824433224433224f0");
 	ms_sends_msg("0559084a32244332244302");
 
+	btw("HLR accepts the IMEI");
+	gsup_rx("32010809710000004026f0510100", NULL);
+
 	btw("a LU Accept with a new TMSI was sent, waiting for TMSI Realloc Compl");
 	EXPECT_CONN_COUNT(1);
 	VERBOSE_ASSERT(lu_result_sent, == RES_ACCEPT, "%d");
diff --git a/tests/msc_vlr/msc_vlr_test_no_authen.err b/tests/msc_vlr/msc_vlr_test_no_authen.err
index 3e28468..3f6d8cd 100644
--- a/tests/msc_vlr/msc_vlr_test_no_authen.err
+++ b/tests/msc_vlr/msc_vlr_test_no_authen.err
@@ -933,16 +933,26 @@
 DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: GSM48_MT_RR_SYSINFO_1
 DRLL Dispatching 04.08 message SMS:0x01 (0x9:0x1)
 DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: SMS:0x01
-- MS replies with an Identity Response
+- MS replies with an Identity Response, VLR sends the IMEI to HLR
   MSC <--GERAN-A-- MS: GSM48_MT_MM_ID_RESP
 DREF IMSI-901700000004620:MSISDN-46071: MSC conn use + dtap == 1 (0x2: dtap)
 DRLL Dispatching 04.08 message GSM48_MT_MM_ID_RESP (0x5:0x19)
 DMM IDENTITY RESPONSE: MI=IMEI-423423423423420
 DVLR set IMEI on subscriber; IMSI=901700000004620 IMEI=423423423423420
 DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_WAIT_LU_COMPL}: Received Event VLR_ULA_E_ID_IMEI
+DVLR GSUP tx: 30010809710000004026f050090824433224433224f0
+GSUP --> HLR: OSMO_GSUP_MSGT_CHECK_IMEI_REQUEST: 30010809710000004026f050090824433224433224f0
+DREF IMSI-901700000004620:MSISDN-46071: MSC conn use - dtap == 0 (0x0: )
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Received Event RAN_CONN_E_UNUSED
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Awaiting results for Auth+Ciph, overruling event RAN_CONN_E_UNUSED
+- HLR accepts the IMEI
+<-- GSUP rx OSMO_GSUP_MSGT_CHECK_IMEI_RESULT: 32010809710000004026f0510100
+DVLR GSUP rx 14: 32010809710000004026f0510100
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage increases to: 2
+DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_WAIT_LU_COMPL}: Received Event VLR_ULA_E_HLR_IMEI_ACK
 DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_WAIT_IMEI}: Received Event LU_COMPL_VLR_E_IMEI_CHECK_ACK
 - sending LU Accept for IMSI-901700000004620:MSISDN-46071
-DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage increases to: 2
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage increases to: 3
 DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_WAIT_IMEI}: state_chg to LU_COMPL_VLR_S_DONE
 DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_WAIT_LU_COMPL}: Received Event VLR_ULA_E_LU_COMPL_SUCCESS
 DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_DONE}: Terminating (cause = OSMO_FSM_TERM_PARENT)
@@ -954,11 +964,12 @@
 DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: state_chg to RAN_CONN_S_ACCEPTED
 DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_ACCEPTED}: Received Event RAN_CONN_E_UNUSED
 DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_ACCEPTED}: state_chg to RAN_CONN_S_RELEASING
-DREF IMSI-901700000004620:MSISDN-46071: MSC conn use + release == 2 (0x102: dtap,release)
-DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage increases to: 3
-DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage decreases to: 2
+DREF IMSI-901700000004620:MSISDN-46071: MSC conn use + release == 1 (0x100: release)
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage increases to: 4
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage decreases to: 3
 - BSSAP Clear --GERAN-A--> MS
-DREF IMSI-901700000004620:MSISDN-46071: MSC conn use - dtap == 1 (0x100: release)
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage decreases to: 2
+<-- GSUP rx OSMO_GSUP_MSGT_CHECK_IMEI_RESULT: vlr_gsupc_read_cb() returns 0
   bssap_clear_sent == 1
 - LU was successful, and the conn has already been closed
   lu_result_sent == 1
@@ -1116,22 +1127,31 @@
 DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: GSM48_MT_RR_SYSINFO_1
 DRLL Dispatching 04.08 message SMS:0x01 (0x9:0x1)
 DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: SMS:0x01
-- MS replies with an Identity Response
+- MS replies with an Identity Response, VLR sends the IMEI to HLR
   MSC <--GERAN-A-- MS: GSM48_MT_MM_ID_RESP
 DREF IMSI-901700000004620:MSISDN-46071: MSC conn use + dtap == 1 (0x2: dtap)
 DRLL Dispatching 04.08 message GSM48_MT_MM_ID_RESP (0x5:0x19)
 DMM IDENTITY RESPONSE: MI=IMEI-423423423423420
 DVLR set IMEI on subscriber; IMSI=901700000004620 IMEI=423423423423420
 DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_WAIT_LU_COMPL}: Received Event VLR_ULA_E_ID_IMEI
+DVLR GSUP tx: 30010809710000004026f050090824433224433224f0
+GSUP --> HLR: OSMO_GSUP_MSGT_CHECK_IMEI_REQUEST: 30010809710000004026f050090824433224433224f0
+DREF IMSI-901700000004620:MSISDN-46071: MSC conn use - dtap == 0 (0x0: )
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Received Event RAN_CONN_E_UNUSED
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Awaiting results for Auth+Ciph, overruling event RAN_CONN_E_UNUSED
+- HLR accepts the IMEI
+<-- GSUP rx OSMO_GSUP_MSGT_CHECK_IMEI_RESULT: 32010809710000004026f0510100
+DVLR GSUP rx 14: 32010809710000004026f0510100
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage increases to: 2
+DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_WAIT_LU_COMPL}: Received Event VLR_ULA_E_HLR_IMEI_ACK
 DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_WAIT_IMEI_TMSI}: Received Event LU_COMPL_VLR_E_IMEI_CHECK_ACK
 DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_WAIT_IMEI_TMSI}: lu_compl_vlr_new_tmsi()
-DVLR SUBSCR(IMSI-901700000004620:MSISDN-46071:TMSInew-0x03020100) VLR: update for IMSI=901700000004620 (MSISDN=46071, used=1)
+DVLR SUBSCR(IMSI-901700000004620:MSISDN-46071:TMSInew-0x03020100) VLR: update for IMSI=901700000004620 (MSISDN=46071, used=2)
 DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:TMSInew-0x03020100:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Updated ID
 DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_WAIT_IMEI_TMSI}: state_chg to LU_COMPL_VLR_S_WAIT_TMSI_CNF
 - sending LU Accept for IMSI-901700000004620:MSISDN-46071:TMSInew-0x03020100, with TMSI 0x03020100
-DREF IMSI-901700000004620:MSISDN-46071:TMSInew-0x03020100: MSC conn use - dtap == 0 (0x0: )
-DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:TMSInew-0x03020100:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Received Event RAN_CONN_E_UNUSED
-DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:TMSInew-0x03020100:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Awaiting results for Auth+Ciph, overruling event RAN_CONN_E_UNUSED
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071:TMSInew-0x03020100 usage decreases to: 1
+<-- GSUP rx OSMO_GSUP_MSGT_CHECK_IMEI_RESULT: vlr_gsupc_read_cb() returns 0
 - a LU Accept with a new TMSI was sent, waiting for TMSI Realloc Compl
   llist_count(&net->ran_conns) == 1
   lu_result_sent == 1
@@ -1516,16 +1536,26 @@
 DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: GSM48_MT_RR_SYSINFO_1
 DRLL Dispatching 04.08 message SMS:0x01 (0x9:0x1)
 DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: SMS:0x01
-- MS replies with an Identity Response
+- MS replies with an Identity Response, VLR sends the IMEI to HLR
   MSC <--GERAN-A-- MS: GSM48_MT_MM_ID_RESP
 DREF IMSI-901700000004620:MSISDN-46071: MSC conn use + dtap == 1 (0x2: dtap)
 DRLL Dispatching 04.08 message GSM48_MT_MM_ID_RESP (0x5:0x19)
 DMM IDENTITY RESPONSE: MI=IMEI-423423423423420
 DVLR set IMEI on subscriber; IMSI=901700000004620 IMEI=423423423423420
 DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_WAIT_LU_COMPL}: Received Event VLR_ULA_E_ID_IMEI
+DVLR GSUP tx: 30010809710000004026f050090824433224433224f0
+GSUP --> HLR: OSMO_GSUP_MSGT_CHECK_IMEI_REQUEST: 30010809710000004026f050090824433224433224f0
+DREF IMSI-901700000004620:MSISDN-46071: MSC conn use - dtap == 0 (0x0: )
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Received Event RAN_CONN_E_UNUSED
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Awaiting results for Auth+Ciph, overruling event RAN_CONN_E_UNUSED
+- HLR accepts the IMEI
+<-- GSUP rx OSMO_GSUP_MSGT_CHECK_IMEI_RESULT: 32010809710000004026f0510100
+DVLR GSUP rx 14: 32010809710000004026f0510100
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage increases to: 2
+DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_WAIT_LU_COMPL}: Received Event VLR_ULA_E_HLR_IMEI_ACK
 DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_WAIT_IMEI}: Received Event LU_COMPL_VLR_E_IMEI_CHECK_ACK
 - sending LU Accept for IMSI-901700000004620:MSISDN-46071
-DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage increases to: 2
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage increases to: 3
 DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_WAIT_IMEI}: state_chg to LU_COMPL_VLR_S_DONE
 DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_WAIT_LU_COMPL}: Received Event VLR_ULA_E_LU_COMPL_SUCCESS
 DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_DONE}: Terminating (cause = OSMO_FSM_TERM_PARENT)
@@ -1537,11 +1567,12 @@
 DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: state_chg to RAN_CONN_S_ACCEPTED
 DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_ACCEPTED}: Received Event RAN_CONN_E_UNUSED
 DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_ACCEPTED}: state_chg to RAN_CONN_S_RELEASING
-DREF IMSI-901700000004620:MSISDN-46071: MSC conn use + release == 2 (0x102: dtap,release)
-DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage increases to: 3
-DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage decreases to: 2
+DREF IMSI-901700000004620:MSISDN-46071: MSC conn use + release == 1 (0x100: release)
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage increases to: 4
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage decreases to: 3
 - BSSAP Clear --GERAN-A--> MS
-DREF IMSI-901700000004620:MSISDN-46071: MSC conn use - dtap == 1 (0x100: release)
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage decreases to: 2
+<-- GSUP rx OSMO_GSUP_MSGT_CHECK_IMEI_RESULT: vlr_gsupc_read_cb() returns 0
   bssap_clear_sent == 1
 - LU was successful, and the conn has already been closed
   lu_result_sent == 1
@@ -2091,22 +2122,31 @@
 DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: GSM48_MT_RR_SYSINFO_1
 DRLL Dispatching 04.08 message SMS:0x01 (0x9:0x1)
 DRLL subscr IMSI-901700000004620:MSISDN-46071: Message not permitted for initial conn: SMS:0x01
-- MS replies with an Identity Response
+- MS replies with an Identity Response, VLR sends the IMEI to HLR
   MSC <--GERAN-A-- MS: GSM48_MT_MM_ID_RESP
 DREF IMSI-901700000004620:MSISDN-46071: MSC conn use + dtap == 1 (0x2: dtap)
 DRLL Dispatching 04.08 message GSM48_MT_MM_ID_RESP (0x5:0x19)
 DMM IDENTITY RESPONSE: MI=IMEI-423423423423420
 DVLR set IMEI on subscriber; IMSI=901700000004620 IMEI=423423423423420
 DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_WAIT_LU_COMPL}: Received Event VLR_ULA_E_ID_IMEI
+DVLR GSUP tx: 30010809710000004026f050090824433224433224f0
+GSUP --> HLR: OSMO_GSUP_MSGT_CHECK_IMEI_REQUEST: 30010809710000004026f050090824433224433224f0
+DREF IMSI-901700000004620:MSISDN-46071: MSC conn use - dtap == 0 (0x0: )
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Received Event RAN_CONN_E_UNUSED
+DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Awaiting results for Auth+Ciph, overruling event RAN_CONN_E_UNUSED
+- HLR accepts the IMEI
+<-- GSUP rx OSMO_GSUP_MSGT_CHECK_IMEI_RESULT: 32010809710000004026f0510100
+DVLR GSUP rx 14: 32010809710000004026f0510100
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071 usage increases to: 2
+DVLR vlr_lu_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){VLR_ULA_S_WAIT_LU_COMPL}: Received Event VLR_ULA_E_HLR_IMEI_ACK
 DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_WAIT_IMEI_TMSI}: Received Event LU_COMPL_VLR_E_IMEI_CHECK_ACK
 DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_WAIT_IMEI_TMSI}: lu_compl_vlr_new_tmsi()
-DVLR SUBSCR(IMSI-901700000004620:MSISDN-46071:TMSInew-0x03020100) VLR: update for IMSI=901700000004620 (MSISDN=46071, used=1)
+DVLR SUBSCR(IMSI-901700000004620:MSISDN-46071:TMSInew-0x03020100) VLR: update for IMSI=901700000004620 (MSISDN=46071, used=2)
 DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:TMSInew-0x03020100:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Updated ID
 DVLR lu_compl_vlr_fsm(IMSI-901700000004620:MSISDN-46071:GERAN-A-0:LU){LU_COMPL_VLR_S_WAIT_IMEI_TMSI}: state_chg to LU_COMPL_VLR_S_WAIT_TMSI_CNF
 - sending LU Accept for IMSI-901700000004620:MSISDN-46071:TMSInew-0x03020100, with TMSI 0x03020100
-DREF IMSI-901700000004620:MSISDN-46071:TMSInew-0x03020100: MSC conn use - dtap == 0 (0x0: )
-DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:TMSInew-0x03020100:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Received Event RAN_CONN_E_UNUSED
-DMM RAN_conn(IMSI-901700000004620:MSISDN-46071:TMSInew-0x03020100:GERAN-A-0:LU){RAN_CONN_S_AUTH_CIPH}: Awaiting results for Auth+Ciph, overruling event RAN_CONN_E_UNUSED
+DREF VLR subscr IMSI-901700000004620:MSISDN-46071:TMSInew-0x03020100 usage decreases to: 1
+<-- GSUP rx OSMO_GSUP_MSGT_CHECK_IMEI_RESULT: vlr_gsupc_read_cb() returns 0
 - a LU Accept with a new TMSI was sent, waiting for TMSI Realloc Compl
   llist_count(&net->ran_conns) == 1
   lu_result_sent == 1