diff --git a/app/nvmf_tgt/conf.c b/app/nvmf_tgt/conf.c
index 44dc7ee87..8c14f61b2 100644
--- a/app/nvmf_tgt/conf.c
+++ b/app/nvmf_tgt/conf.c
@@ -117,7 +117,7 @@ spdk_add_nvmf_discovery_subsystem(void)
 {
 	struct nvmf_tgt_subsystem *app_subsys;
 
-	app_subsys = nvmf_tgt_create_subsystem(SPDK_NVMF_DISCOVERY_NQN, SPDK_NVMF_SUBTYPE_DISCOVERY,
+	app_subsys = nvmf_tgt_create_subsystem(SPDK_NVMF_DISCOVERY_NQN, SPDK_NVMF_SUBTYPE_DISCOVERY, 0,
 					       g_spdk_nvmf_tgt_conf.acceptor_lcore);
 	if (app_subsys == NULL) {
 		SPDK_ERRLOG("Failed creating discovery nvmf library subsystem\n");
@@ -392,7 +392,7 @@ spdk_nvmf_construct_subsystem(const char *name, int32_t lcore,
 	lcore = spdk_nvmf_allocate_lcore(mask, lcore);
 	g_last_core = lcore;
 
-	app_subsys = nvmf_tgt_create_subsystem(name, SPDK_NVMF_SUBTYPE_NVME, lcore);
+	app_subsys = nvmf_tgt_create_subsystem(name, SPDK_NVMF_SUBTYPE_NVME, num_devs, lcore);
 	if (app_subsys == NULL) {
 		SPDK_ERRLOG("Subsystem creation failed\n");
 		return -1;
diff --git a/app/nvmf_tgt/nvmf_tgt.c b/app/nvmf_tgt/nvmf_tgt.c
index 8670b703e..d78a07d89 100644
--- a/app/nvmf_tgt/nvmf_tgt.c
+++ b/app/nvmf_tgt/nvmf_tgt.c
@@ -185,7 +185,7 @@ nvmf_tgt_start_subsystem(struct nvmf_tgt_subsystem *app_subsys)
 }
 
 struct nvmf_tgt_subsystem *
-nvmf_tgt_create_subsystem(const char *name, enum spdk_nvmf_subtype subtype,
+nvmf_tgt_create_subsystem(const char *name, enum spdk_nvmf_subtype subtype, uint32_t num_ns,
 			  uint32_t lcore)
 {
 	struct spdk_nvmf_subsystem *subsystem;
@@ -202,7 +202,7 @@ nvmf_tgt_create_subsystem(const char *name, enum spdk_nvmf_subtype subtype,
 		return NULL;
 	}
 
-	subsystem = spdk_nvmf_create_subsystem(g_tgt, name, subtype, app_subsys, connect_cb,
+	subsystem = spdk_nvmf_create_subsystem(g_tgt, name, subtype, num_ns, app_subsys, connect_cb,
 					       disconnect_cb);
 	if (subsystem == NULL) {
 		SPDK_ERRLOG("Subsystem creation failed\n");
diff --git a/app/nvmf_tgt/nvmf_tgt.h b/app/nvmf_tgt/nvmf_tgt.h
index e6c889f53..fd1726b3b 100644
--- a/app/nvmf_tgt/nvmf_tgt.h
+++ b/app/nvmf_tgt/nvmf_tgt.h
@@ -76,7 +76,7 @@ int spdk_nvmf_parse_conf(void);
 void nvmf_tgt_start_subsystem(struct nvmf_tgt_subsystem *subsystem);
 
 struct nvmf_tgt_subsystem *nvmf_tgt_create_subsystem(const char *name,
-		enum spdk_nvmf_subtype subtype,
+		enum spdk_nvmf_subtype subtype, uint32_t num_ns,
 		uint32_t lcore);
 
 int
diff --git a/include/spdk/nvmf.h b/include/spdk/nvmf.h
index de75ea92b..df4ba709f 100644
--- a/include/spdk/nvmf.h
+++ b/include/spdk/nvmf.h
@@ -45,8 +45,6 @@
 #include "spdk/nvmf_spec.h"
 #include "spdk/queue.h"
 
-#define MAX_VIRTUAL_NAMESPACE 16
-
 struct spdk_nvmf_tgt;
 
 struct spdk_nvmf_tgt_opts {
@@ -113,6 +111,7 @@ struct spdk_nvmf_listen_addr {
 struct spdk_nvmf_subsystem *spdk_nvmf_create_subsystem(struct spdk_nvmf_tgt *tgt,
 		const char *nqn,
 		enum spdk_nvmf_subtype type,
+		uint32_t num_ns,
 		void *cb_ctx,
 		spdk_nvmf_subsystem_connect_fn connect_cb,
 		spdk_nvmf_subsystem_disconnect_fn disconnect_cb);
diff --git a/lib/nvmf/nvmf_internal.h b/lib/nvmf/nvmf_internal.h
index c95f2a449..a32b61bf3 100644
--- a/lib/nvmf/nvmf_internal.h
+++ b/lib/nvmf/nvmf_internal.h
@@ -90,8 +90,10 @@ struct spdk_nvmf_subsystem {
 
 	char sn[SPDK_NVME_CTRLR_SN_LEN + 1];
 
-	struct spdk_nvmf_ns			ns[MAX_VIRTUAL_NAMESPACE];
+	/* Array of namespaces of size max_nsid indexed by nsid - 1 */
+	struct spdk_nvmf_ns			*ns;
 	uint32_t 				max_nsid;
+	uint32_t				num_allocated_nsid;
 
 	void					*cb_ctx;
 	spdk_nvmf_subsystem_connect_fn		connect_cb;
diff --git a/lib/nvmf/subsystem.c b/lib/nvmf/subsystem.c
index a136ffb52..c6acc95ff 100644
--- a/lib/nvmf/subsystem.c
+++ b/lib/nvmf/subsystem.c
@@ -133,6 +133,7 @@ struct spdk_nvmf_subsystem *
 spdk_nvmf_create_subsystem(struct spdk_nvmf_tgt *tgt,
 			   const char *nqn,
 			   enum spdk_nvmf_subtype type,
+			   uint32_t num_ns,
 			   void *cb_ctx,
 			   spdk_nvmf_subsystem_connect_fn connect_cb,
 			   spdk_nvmf_subsystem_disconnect_fn disconnect_cb)
@@ -143,6 +144,11 @@ spdk_nvmf_create_subsystem(struct spdk_nvmf_tgt *tgt,
 		return NULL;
 	}
 
+	if (type == SPDK_NVMF_SUBTYPE_DISCOVERY && num_ns != 0) {
+		SPDK_ERRLOG("Discovery subsystem cannot have namespaces.\n");
+		return NULL;
+	}
+
 	subsystem = calloc(1, sizeof(struct spdk_nvmf_subsystem));
 	if (subsystem == NULL) {
 		return NULL;
@@ -154,6 +160,8 @@ spdk_nvmf_create_subsystem(struct spdk_nvmf_tgt *tgt,
 
 	subsystem->id = tgt->current_subsystem_id;
 	subsystem->subtype = type;
+	subsystem->max_nsid = num_ns;
+	subsystem->num_allocated_nsid = 0;
 	subsystem->cb_ctx = cb_ctx;
 	subsystem->connect_cb = connect_cb;
 	subsystem->disconnect_cb = disconnect_cb;
@@ -162,6 +170,15 @@ spdk_nvmf_create_subsystem(struct spdk_nvmf_tgt *tgt,
 	TAILQ_INIT(&subsystem->hosts);
 	TAILQ_INIT(&subsystem->ctrlrs);
 
+	if (num_ns != 0) {
+		subsystem->ns = calloc(num_ns, sizeof(struct spdk_nvmf_ns));
+		if (subsystem->ns == NULL) {
+			SPDK_ERRLOG("Namespace memory allocation failed\n");
+			free(subsystem);
+			return NULL;
+		}
+	}
+
 	TAILQ_INSERT_TAIL(&tgt->subsystems, subsystem, entries);
 	tgt->discovery_genctr++;
 
@@ -198,6 +215,8 @@ spdk_nvmf_delete_subsystem(struct spdk_nvmf_subsystem *subsystem)
 
 	spdk_nvmf_subsystem_bdev_detach(subsystem);
 
+	free(subsystem->ns);
+
 	TAILQ_REMOVE(&subsystem->tgt->subsystems, subsystem, entries);
 	subsystem->tgt->discovery_genctr++;
 
@@ -348,9 +367,37 @@ spdk_nvmf_subsystem_add_ns(struct spdk_nvmf_subsystem *subsystem, struct spdk_bd
 	uint32_t i;
 	int rc;
 
+	if (nsid > subsystem->max_nsid ||
+	    (nsid == 0 && subsystem->num_allocated_nsid == subsystem->max_nsid)) {
+		struct spdk_nvmf_ns *new_ns_array;
+		uint32_t new_max_nsid;
+
+		if (nsid > subsystem->max_nsid) {
+			new_max_nsid = nsid;
+		} else {
+			new_max_nsid = subsystem->max_nsid + 1;
+		}
+
+		if (!TAILQ_EMPTY(&subsystem->ctrlrs)) {
+			SPDK_ERRLOG("Can't extend NSID range with active connections\n");
+			return 0;
+		}
+
+		new_ns_array = realloc(subsystem->ns, sizeof(struct spdk_nvmf_ns) * new_max_nsid);
+		if (new_ns_array == NULL) {
+			SPDK_ERRLOG("Memory allocation error while resizing namespace array.\n");
+			return 0;
+		}
+
+		memset(new_ns_array + subsystem->max_nsid, 0,
+		       sizeof(struct spdk_nvmf_ns) * (new_max_nsid - subsystem->max_nsid));
+		subsystem->ns = new_ns_array;
+		subsystem->max_nsid = new_max_nsid;
+	}
+
 	if (nsid == 0) {
 		/* NSID not specified - find a free index */
-		for (i = 0; i < MAX_VIRTUAL_NAMESPACE; i++) {
+		for (i = 0; i < subsystem->max_nsid; i++) {
 			if (_spdk_nvmf_subsystem_get_ns(subsystem, i + 1) == NULL) {
 				nsid = i + 1;
 				break;
@@ -362,19 +409,13 @@ spdk_nvmf_subsystem_add_ns(struct spdk_nvmf_subsystem *subsystem, struct spdk_bd
 		}
 	} else {
 		/* Specific NSID requested */
-		i = nsid - 1;
-		if (i >= MAX_VIRTUAL_NAMESPACE) {
-			SPDK_ERRLOG("Requested NSID %" PRIu32 " out of range\n", nsid);
-			return 0;
-		}
-
 		if (_spdk_nvmf_subsystem_get_ns(subsystem, nsid)) {
 			SPDK_ERRLOG("Requested NSID %" PRIu32 " already in use\n", nsid);
 			return 0;
 		}
 	}
 
-	ns = &subsystem->ns[i];
+	ns = &subsystem->ns[nsid - 1];
 	memset(ns, 0, sizeof(*ns));
 	ns->bdev = bdev;
 	ns->id = nsid;
@@ -392,6 +433,7 @@ spdk_nvmf_subsystem_add_ns(struct spdk_nvmf_subsystem *subsystem, struct spdk_bd
 		      nsid);
 
 	subsystem->max_nsid = spdk_max(subsystem->max_nsid, nsid);
+	subsystem->num_allocated_nsid++;
 	return nsid;
 }
 
diff --git a/test/unit/lib/nvmf/ctrlr_discovery.c/ctrlr_discovery_ut.c b/test/unit/lib/nvmf/ctrlr_discovery.c/ctrlr_discovery_ut.c
index 45bf49191..b82bc7b2c 100644
--- a/test/unit/lib/nvmf/ctrlr_discovery.c/ctrlr_discovery_ut.c
+++ b/test/unit/lib/nvmf/ctrlr_discovery.c/ctrlr_discovery_ut.c
@@ -196,7 +196,7 @@ test_discovery_log(void)
 
 	/* Add one subsystem and verify that the discovery log contains it */
 	subsystem = spdk_nvmf_create_subsystem(&g_nvmf_tgt, "nqn.2016-06.io.spdk:subsystem1",
-					       SPDK_NVMF_SUBTYPE_NVME,
+					       SPDK_NVMF_SUBTYPE_NVME, 0,
 					       NULL, NULL, NULL);
 	SPDK_CU_ASSERT_FATAL(subsystem != NULL);
 
diff --git a/test/unit/lib/nvmf/subsystem.c/subsystem_ut.c b/test/unit/lib/nvmf/subsystem.c/subsystem_ut.c
index fd1f95f53..74c17f4c6 100644
--- a/test/unit/lib/nvmf/subsystem.c/subsystem_ut.c
+++ b/test/unit/lib/nvmf/subsystem.c/subsystem_ut.c
@@ -190,7 +190,7 @@ test_spdk_nvmf_subsystem_add_ns(void)
 {
 	struct spdk_nvmf_subsystem subsystem = {
 		.max_nsid = 0,
-		.ns = {},
+		.ns = NULL,
 	};
 	struct spdk_bdev bdev1 = {}, bdev2 = {};
 	uint32_t nsid;
@@ -212,6 +212,8 @@ test_spdk_nvmf_subsystem_add_ns(void)
 	nsid = spdk_nvmf_subsystem_add_ns(&subsystem, &bdev2, 5);
 	CU_ASSERT(nsid == 0);
 	CU_ASSERT(subsystem.max_nsid == 5);
+
+	free(subsystem.ns);
 }
 
 static void
@@ -223,7 +225,7 @@ nvmf_test_create_subsystem(void)
 	TAILQ_INIT(&tgt.subsystems);
 
 	strncpy(nqn, "nqn.2016-06.io.spdk:subsystem1", sizeof(nqn));
-	subsystem = spdk_nvmf_create_subsystem(&tgt, nqn, SPDK_NVMF_SUBTYPE_NVME,
+	subsystem = spdk_nvmf_create_subsystem(&tgt, nqn, SPDK_NVMF_SUBTYPE_NVME, 0,
 					       NULL, NULL, NULL);
 	SPDK_CU_ASSERT_FATAL(subsystem != NULL);
 	CU_ASSERT_STRING_EQUAL(subsystem->subnqn, nqn);
@@ -234,7 +236,7 @@ nvmf_test_create_subsystem(void)
 	memset(nqn + strlen(nqn), 'a', 223 - strlen(nqn));
 	nqn[223] = '\0';
 	CU_ASSERT(strlen(nqn) == 223);
-	subsystem = spdk_nvmf_create_subsystem(&tgt, nqn, SPDK_NVMF_SUBTYPE_NVME,
+	subsystem = spdk_nvmf_create_subsystem(&tgt, nqn, SPDK_NVMF_SUBTYPE_NVME, 0,
 					       NULL, NULL, NULL);
 	SPDK_CU_ASSERT_FATAL(subsystem != NULL);
 	CU_ASSERT_STRING_EQUAL(subsystem->subnqn, nqn);
@@ -245,7 +247,7 @@ nvmf_test_create_subsystem(void)
 	memset(nqn + strlen(nqn), 'a', 224 - strlen(nqn));
 	nqn[224] = '\0';
 	CU_ASSERT(strlen(nqn) == 224);
-	subsystem = spdk_nvmf_create_subsystem(&tgt, nqn, SPDK_NVMF_SUBTYPE_NVME,
+	subsystem = spdk_nvmf_create_subsystem(&tgt, nqn, SPDK_NVMF_SUBTYPE_NVME, 0,
 					       NULL, NULL, NULL);
 	CU_ASSERT(subsystem == NULL);
 }