diff --git a/lib/iscsi/iscsi_rpc.c b/lib/iscsi/iscsi_rpc.c
index a02d8e98f..236b372ca 100644
--- a/lib/iscsi/iscsi_rpc.c
+++ b/lib/iscsi/iscsi_rpc.c
@@ -826,7 +826,8 @@ spdk_rpc_add_portal_group(struct spdk_jsonrpc_request *request,
 			  const struct spdk_json_val *params)
 {
 	struct rpc_portal_group req = {};
-	struct spdk_iscsi_portal *portal_list[MAX_PORTAL] = {};
+	struct spdk_iscsi_portal_grp *pg = NULL;
+	struct spdk_iscsi_portal *portal;
 	struct spdk_json_write_ctx *w;
 	size_t i = 0;
 	int rc = -1;
@@ -838,21 +839,31 @@ spdk_rpc_add_portal_group(struct spdk_jsonrpc_request *request,
 		goto out;
 	}
 
+	pg = spdk_iscsi_portal_grp_create(req.tag);
+	if (pg == NULL) {
+		SPDK_ERRLOG("portal_grp_create failed\n");
+		goto out;
+	}
 	for (i = 0; i < req.portal_list.num_portals; i++) {
-		portal_list[i] = spdk_iscsi_portal_create(req.portal_list.portals[i].host,
-				 req.portal_list.portals[i].port,
-				 req.portal_list.portals[i].cpumask);
-		if (portal_list[i] == NULL) {
-			SPDK_ERRLOG("portal_list allocation failed\n");
+		portal = spdk_iscsi_portal_create(req.portal_list.portals[i].host,
+						  req.portal_list.portals[i].port,
+						  req.portal_list.portals[i].cpumask);
+		if (portal == NULL) {
+			SPDK_ERRLOG("portal_create failed\n");
 			goto out;
 		}
+		spdk_iscsi_portal_grp_add_portal(pg, portal);
 	}
 
-	rc = spdk_iscsi_portal_grp_create_from_portal_list(req.tag, portal_list,
-			req.portal_list.num_portals);
+	rc = spdk_iscsi_portal_grp_open(pg);
+	if (rc != 0) {
+		SPDK_ERRLOG("portal_grp_open failed\n");
+		goto out;
+	}
 
-	if (rc < 0) {
-		SPDK_ERRLOG("create_from_portal_list failed\n");
+	rc = spdk_iscsi_portal_grp_register(pg);
+	if (rc != 0) {
+		SPDK_ERRLOG("portal_grp_register failed\n");
 	}
 
 out:
@@ -865,8 +876,8 @@ out:
 	} else {
 		spdk_jsonrpc_send_error_response(request, SPDK_JSONRPC_ERROR_INVALID_PARAMS, "Invalid parameters");
 
-		for (; i > 0; --i) {
-			spdk_iscsi_portal_destroy(portal_list[i - 1]);
+		if (pg != NULL) {
+			spdk_iscsi_portal_grp_release(pg);
 		}
 	}
 	free_rpc_portal_group(&req);
diff --git a/lib/iscsi/iscsi_subsystem.c b/lib/iscsi/iscsi_subsystem.c
index c63d75ae0..1155d9aa2 100644
--- a/lib/iscsi/iscsi_subsystem.c
+++ b/lib/iscsi/iscsi_subsystem.c
@@ -815,19 +815,6 @@ spdk_iscsi_app_read_parameters(void)
 	return 0;
 }
 
-static void
-spdk_iscsi_setup(void *arg1, void *arg2)
-{
-	int rc;
-
-	/* open portals */
-	rc = spdk_iscsi_portal_grp_open_all();
-	if (rc < 0) {
-		SPDK_ERRLOG("spdk_iscsi_portal_grp_open_all() failed\n");
-		return;
-	}
-}
-
 int
 spdk_iscsi_init(void)
 {
@@ -857,11 +844,6 @@ spdk_iscsi_init(void)
 		return -1;
 	}
 
-	/*
-	 * Defer creation of listening sockets until the reactor has started.
-	 */
-	spdk_event_call(spdk_event_allocate(spdk_env_get_current_core(), spdk_iscsi_setup, NULL, NULL));
-
 	return 0;
 }
 
diff --git a/lib/iscsi/portal_grp.c b/lib/iscsi/portal_grp.c
index 761905598..2fdbf8f63 100644
--- a/lib/iscsi/portal_grp.c
+++ b/lib/iscsi/portal_grp.c
@@ -48,9 +48,6 @@
 
 #define PORTNUMSTRLEN 32
 
-static int
-spdk_iscsi_portal_grp_open(struct spdk_iscsi_portal_grp *pg);
-
 static struct spdk_iscsi_portal *
 spdk_iscsi_portal_find_by_addr(const char *host, const char *port)
 {
@@ -195,6 +192,13 @@ spdk_iscsi_portal_open(struct spdk_iscsi_portal *p)
 
 	p->sock = sock;
 
+	/*
+	 * When the portal is created by config file, incoming connection
+	 * requests for the socket are pended to accept until reactors start.
+	 * However the gap between listen() and accept() will be slight and
+	 * the requests will be queued by the nonzero backlog of the socket
+	 * or resend by TCP.
+	 */
 	spdk_iscsi_acceptor_start(p);
 
 	return 0;
@@ -326,7 +330,7 @@ error_out:
 	return rc;
 }
 
-static struct spdk_iscsi_portal_grp *
+struct spdk_iscsi_portal_grp *
 spdk_iscsi_portal_grp_create(int tag)
 {
 	struct spdk_iscsi_portal_grp *pg = malloc(sizeof(*pg));
@@ -344,7 +348,7 @@ spdk_iscsi_portal_grp_create(int tag)
 	return pg;
 }
 
-static void
+void
 spdk_iscsi_portal_grp_destroy(struct spdk_iscsi_portal_grp *pg)
 {
 	struct spdk_iscsi_portal	*p;
@@ -360,14 +364,13 @@ spdk_iscsi_portal_grp_destroy(struct spdk_iscsi_portal_grp *pg)
 	free(pg);
 }
 
-static int
+int
 spdk_iscsi_portal_grp_register(struct spdk_iscsi_portal_grp *pg)
 {
 	int rc = -1;
 	struct spdk_iscsi_portal_grp *tmp;
 
 	assert(pg != NULL);
-	assert(!TAILQ_EMPTY(&pg->head));
 
 	pthread_mutex_lock(&g_spdk_iscsi.mutex);
 	tmp = spdk_iscsi_portal_grp_find_by_tag(pg->tag);
@@ -379,7 +382,7 @@ spdk_iscsi_portal_grp_register(struct spdk_iscsi_portal_grp *pg)
 	return rc;
 }
 
-static void
+void
 spdk_iscsi_portal_grp_add_portal(struct spdk_iscsi_portal_grp *pg,
 				 struct spdk_iscsi_portal *p)
 {
@@ -390,71 +393,11 @@ spdk_iscsi_portal_grp_add_portal(struct spdk_iscsi_portal_grp *pg,
 	TAILQ_INSERT_TAIL(&pg->head, p, per_pg_tailq);
 }
 
-/**
- * If all portals are valid, this function will take their ownership.
- */
-int
-spdk_iscsi_portal_grp_create_from_portal_list(int tag,
-		struct spdk_iscsi_portal **portal_list,
-		int num_portals)
-{
-	int i = 0, rc = 0;
-	struct spdk_iscsi_portal_grp *pg;
-
-	SPDK_DEBUGLOG(SPDK_LOG_ISCSI, "add portal group (from portal list) %d\n", tag);
-
-	if (num_portals > MAX_PORTAL) {
-		SPDK_ERRLOG("%d > MAX_PORTAL\n", num_portals);
-		return -1;
-	}
-
-	pg = spdk_iscsi_portal_grp_create(tag);
-	if (!pg) {
-		SPDK_ERRLOG("portal group creation error (%d)\n", tag);
-		return -1;
-	}
-
-	for (i = 0; i < num_portals; i++) {
-		struct spdk_iscsi_portal *p = portal_list[i];
-
-		SPDK_DEBUGLOG(SPDK_LOG_ISCSI,
-			      "RIndex=%d, Host=%s, Port=%s, Tag=%d\n",
-			      i, p->host, p->port, tag);
-		rc = spdk_iscsi_portal_open(p);
-		if (rc < 0) {
-			/* if listening failed on any port, do not register the portal group
-			 * and close any previously opened. */
-			for (--i; i >= 0; --i) {
-				spdk_iscsi_portal_close(portal_list[i]);
-			}
-
-			break;
-		}
-	}
-
-	if (rc < 0) {
-		spdk_iscsi_portal_grp_destroy(pg);
-	} else {
-		/* Add portals to portal group */
-		for (i = 0; i < num_portals; i++) {
-			spdk_iscsi_portal_grp_add_portal(pg, portal_list[i]);
-		}
-
-		/* Add portal group to the end of the pg list */
-		rc = spdk_iscsi_portal_grp_register(pg);
-		if (rc != 0) {
-			spdk_iscsi_portal_grp_destroy(pg);
-		}
-	}
-
-	return rc;
-}
-
 static int
 spdk_iscsi_portal_grp_create_from_configfile(struct spdk_conf_section *sp)
 {
 	struct spdk_iscsi_portal_grp *pg;
-	struct spdk_iscsi_portal	*p;
+	struct spdk_iscsi_portal *p;
 	const char *val;
 	char *label, *portal;
 	int portals = 0, i = 0, rc = 0;
@@ -502,16 +445,14 @@ spdk_iscsi_portal_grp_create_from_configfile(struct spdk_conf_section *sp)
 		label = spdk_conf_section_get_nmval(sp, "Portal", i, 0);
 		portal = spdk_conf_section_get_nmval(sp, "Portal", i, 1);
 		if (label == NULL || portal == NULL) {
-			spdk_iscsi_portal_grp_destroy(pg);
 			SPDK_ERRLOG("portal error\n");
-			return -1;
+			goto error;
 		}
 
 		rc = spdk_iscsi_portal_create_from_configline(portal, &p, 0);
 		if (rc < 0) {
-			spdk_iscsi_portal_grp_destroy(pg);
 			SPDK_ERRLOG("parse portal error (%s)\n", portal);
-			return -1;
+			goto error;
 		}
 
 		SPDK_DEBUGLOG(SPDK_LOG_ISCSI,
@@ -521,15 +462,24 @@ spdk_iscsi_portal_grp_create_from_configfile(struct spdk_conf_section *sp)
 		spdk_iscsi_portal_grp_add_portal(pg, p);
 	}
 
+	rc = spdk_iscsi_portal_grp_open(pg);
+	if (rc != 0) {
+		SPDK_ERRLOG("portal_grp_open failed\n");
+		goto error;
+	}
+
 	/* Add portal group to the end of the pg list */
 	rc = spdk_iscsi_portal_grp_register(pg);
 	if (rc != 0) {
 		SPDK_ERRLOG("register portal failed\n");
-		spdk_iscsi_portal_grp_destroy(pg);
-		return -1;
+		goto error;
 	}
 
 	return 0;
+
+error:
+	spdk_iscsi_portal_grp_release(pg);
+	return -1;
 }
 
 struct spdk_iscsi_portal_grp *
@@ -591,7 +541,7 @@ spdk_iscsi_portal_grp_array_destroy(void)
 	pthread_mutex_unlock(&g_spdk_iscsi.mutex);
 }
 
-static int
+int
 spdk_iscsi_portal_grp_open(struct spdk_iscsi_portal_grp *pg)
 {
 	struct spdk_iscsi_portal *p;
@@ -606,25 +556,6 @@ spdk_iscsi_portal_grp_open(struct spdk_iscsi_portal_grp *pg)
 	return 0;
 }
 
-int
-spdk_iscsi_portal_grp_open_all(void)
-{
-	struct spdk_iscsi_portal_grp *pg;
-	int rc;
-
-	SPDK_DEBUGLOG(SPDK_LOG_ISCSI, "spdk_iscsi_portal_grp_open_all\n");
-	pthread_mutex_lock(&g_spdk_iscsi.mutex);
-	TAILQ_FOREACH(pg, &g_spdk_iscsi.pg_head, tailq) {
-		rc = spdk_iscsi_portal_grp_open(pg);
-		if (rc < 0) {
-			pthread_mutex_unlock(&g_spdk_iscsi.mutex);
-			return -1;
-		}
-	}
-	pthread_mutex_unlock(&g_spdk_iscsi.mutex);
-	return 0;
-}
-
 static void
 spdk_iscsi_portal_grp_close(struct spdk_iscsi_portal_grp *pg)
 {
diff --git a/lib/iscsi/portal_grp.h b/lib/iscsi/portal_grp.h
index ce030d86b..39e72899d 100644
--- a/lib/iscsi/portal_grp.h
+++ b/lib/iscsi/portal_grp.h
@@ -62,15 +62,17 @@ struct spdk_iscsi_portal *spdk_iscsi_portal_create(const char *host, const char
 		const char *cpumask);
 void spdk_iscsi_portal_destroy(struct spdk_iscsi_portal *p);
 
-int spdk_iscsi_portal_grp_create_from_portal_list(int tag,
-		struct spdk_iscsi_portal **portal_list,
-		int num_portals);
+struct spdk_iscsi_portal_grp *spdk_iscsi_portal_grp_create(int tag);
+void spdk_iscsi_portal_grp_add_portal(struct spdk_iscsi_portal_grp *pg,
+				      struct spdk_iscsi_portal *p);
+void spdk_iscsi_portal_grp_destroy(struct spdk_iscsi_portal_grp *pg);
 void spdk_iscsi_portal_grp_release(struct spdk_iscsi_portal_grp *pg);
 int spdk_iscsi_portal_grp_array_create(void);
 void spdk_iscsi_portal_grp_array_destroy(void);
+int spdk_iscsi_portal_grp_register(struct spdk_iscsi_portal_grp *pg);
 struct spdk_iscsi_portal_grp *spdk_iscsi_portal_grp_unregister(int tag);
 struct spdk_iscsi_portal_grp *spdk_iscsi_portal_grp_find_by_tag(int tag);
+int spdk_iscsi_portal_grp_open(struct spdk_iscsi_portal_grp *pg);
 
-int spdk_iscsi_portal_grp_open_all(void);
 void spdk_iscsi_portal_grp_close_all(void);
 #endif // SPDK_PORTAL_GRP_H
diff --git a/test/unit/lib/iscsi/portal_grp.c/portal_grp_ut.c b/test/unit/lib/iscsi/portal_grp.c/portal_grp_ut.c
index 8e401198d..432f9ec32 100644
--- a/test/unit/lib/iscsi/portal_grp.c/portal_grp_ut.c
+++ b/test/unit/lib/iscsi/portal_grp.c/portal_grp_ut.c
@@ -371,6 +371,43 @@ portal_grp_register_twice_case(void)
 	CU_ASSERT(TAILQ_EMPTY(&g_spdk_iscsi.portal_head));
 }
 
+static void
+portal_grp_add_delete_case(void)
+{
+	struct spdk_iscsi_portal_grp *pg1, *pg2;
+	struct spdk_iscsi_portal *p;
+	int rc;
+
+	const char *host = "192.168.2.0";
+	const char *port = "3260";
+	const char *cpumask = "1";
+
+	/* internal of add_portal_group */
+	pg1 = spdk_iscsi_portal_grp_create(1);
+	CU_ASSERT(pg1 != NULL);
+
+	p = spdk_iscsi_portal_create(host, port, cpumask);
+	CU_ASSERT(p != NULL);
+
+	spdk_iscsi_portal_grp_add_portal(pg1, p);
+
+	rc = spdk_iscsi_portal_grp_open(pg1);
+	CU_ASSERT(rc == 0);
+
+	rc = spdk_iscsi_portal_grp_register(pg1);
+	CU_ASSERT(rc == 0);
+
+	/* internal of delete_portal_group */
+	pg2 = spdk_iscsi_portal_grp_unregister(1);
+	CU_ASSERT(pg2 != NULL);
+	CU_ASSERT(pg1 == pg2);
+
+	spdk_iscsi_portal_grp_release(pg2);
+
+	CU_ASSERT(TAILQ_EMPTY(&g_spdk_iscsi.portal_head));
+	CU_ASSERT(TAILQ_EMPTY(&g_spdk_iscsi.pg_head));
+}
+
 int
 main(int argc, char **argv)
 {
@@ -418,6 +455,8 @@ main(int argc, char **argv)
 			       portal_grp_register_unregister_case) == NULL
 		|| CU_add_test(suite, "portal group register twice case",
 			       portal_grp_register_twice_case) == NULL
+		|| CU_add_test(suite, "portal group add/delete case",
+			       portal_grp_add_delete_case) == NULL
 	) {
 		CU_cleanup_registry();
 		return CU_get_error();