diff --git a/usr/src/uts/common/io/aggr/aggr_grp.c b/usr/src/uts/common/io/aggr/aggr_grp.c
index a4cfdad51ecd..0c284c6d4c9c 100644
--- a/usr/src/uts/common/io/aggr/aggr_grp.c
+++ b/usr/src/uts/common/io/aggr/aggr_grp.c
@@ -227,6 +227,8 @@ aggr_grp_destructor(void *buf, void *arg)
 		    grp->lg_tx_ports_size * sizeof (aggr_port_t *));
 	}
 
+	kmem_free(grp->lg_rx_groups, grp->lg_rx_groups_size);
+
 	mutex_destroy(&grp->lg_lacp_lock);
 	cv_destroy(&grp->lg_lacp_cv);
 	mutex_destroy(&grp->lg_port_lock);
@@ -753,7 +755,7 @@ aggr_add_pseudo_rx_group(aggr_port_t *port, aggr_pseudo_rx_group_t *rx_grp)
 	uint_t			g_idx = rx_grp->arg_index;
 
 	ASSERT(MAC_PERIM_HELD(port->lp_grp->lg_mh));
-	ASSERT3U(g_idx, <, MAX_GROUPS_PER_PORT);
+	ASSERT3U(g_idx, <, port->lp_grp->lg_rx_group_count);
 	mac_perim_enter_by_mh(port->lp_mh, &pmph);
 
 	i = 0;
@@ -836,7 +838,7 @@ aggr_rem_pseudo_rx_group(aggr_port_t *port, aggr_pseudo_rx_group_t *rx_grp)
 	uint_t			g_idx = rx_grp->arg_index;
 
 	ASSERT(MAC_PERIM_HELD(port->lp_grp->lg_mh));
-	ASSERT3U(g_idx, <, MAX_GROUPS_PER_PORT);
+	ASSERT3U(g_idx, <, port->lp_grp->lg_rx_group_count);
 	ASSERT3P(rx_grp->arg_gh, !=, NULL);
 	mac_perim_enter_by_mh(port->lp_mh, &pmph);
 
@@ -1491,8 +1493,6 @@ aggr_grp_create(datalink_id_t linkid, uint32_t key, uint_t nports,
 	grp->lg_tx_blocked_rings = kmem_zalloc((sizeof (mac_ring_handle_t *) *
 	    MAX_RINGS_PER_GROUP), KM_SLEEP);
 	grp->lg_tx_blocked_cnt = 0;
-	bzero(&grp->lg_rx_groups,
-	    sizeof (aggr_pseudo_rx_group_t) * MAX_GROUPS_PER_PORT);
 	bzero(&grp->lg_tx_group, sizeof (aggr_pseudo_tx_group_t));
 	aggr_lacp_init_grp(grp);
 
@@ -1537,16 +1537,12 @@ aggr_grp_create(datalink_id_t linkid, uint32_t key, uint_t nports,
 		    num_rgroups);
 	}
 
-	/*
-	 * There could be cases where the hardware provides more
-	 * groups than aggr can support. Make sure we never go above
-	 * the max aggr can support.
-	 */
-	grp->lg_rx_group_count = MIN(grp->lg_rx_group_count,
-	    MAX_GROUPS_PER_PORT);
+	grp->lg_rx_groups_size = sizeof (aggr_pseudo_rx_group_t) *
+	    grp->lg_rx_group_count;
+	grp->lg_rx_groups = kmem_zalloc(grp->lg_rx_groups_size, KM_SLEEP);
 
 	ASSERT3U(grp->lg_rx_group_count, >, 0);
-	for (i = 0; i < MAX_GROUPS_PER_PORT; i++) {
+	for (i = 0; i < grp->lg_rx_group_count; i++) {
 		grp->lg_rx_groups[i].arg_index = i;
 		grp->lg_rx_groups[i].arg_untagged = 0;
 		list_create(&(grp->lg_rx_groups[i].arg_vlans),
@@ -2120,7 +2116,7 @@ aggr_grp_delete(datalink_id_t linkid, cred_t *cred)
 	VERIFY(mac_unregister(grp->lg_mh) == 0);
 	grp->lg_mh = NULL;
 
-	for (uint_t i = 0; i < MAX_GROUPS_PER_PORT; i++) {
+	for (uint_t i = 0; i < grp->lg_rx_group_count; i++) {
 		list_destroy(&(grp->lg_rx_groups[i].arg_vlans));
 	}
 
diff --git a/usr/src/uts/common/io/aggr/aggr_port.c b/usr/src/uts/common/io/aggr/aggr_port.c
index e764dd104e6e..5384a5817e8c 100644
--- a/usr/src/uts/common/io/aggr/aggr_port.c
+++ b/usr/src/uts/common/io/aggr/aggr_port.c
@@ -73,8 +73,9 @@ aggr_port_destructor(void *buf, void *arg)
 
 	ASSERT3P(port->lp_mnh, ==, NULL);
 	ASSERT(!port->lp_tx_grp_added);
-	for (uint_t i = 0; i < MAX_GROUPS_PER_PORT; i++)
+	for (uint_t i = 0; i < port->lp_hwgh_count; i++)
 		ASSERT3P(port->lp_hwghs[i], ==, NULL);
+	kmem_free(port->lp_hwghs, port->lp_hwghs_size);
 }
 
 void
@@ -147,6 +148,8 @@ aggr_port_create(aggr_grp_t *grp, const datalink_id_t linkid, boolean_t force,
 	char port_name[MAXNAMELEN];
 	mac_diag_t diag;
 	mac_unicast_handle_t mah;
+	mac_perim_handle_t mph;
+	uint_t num_rgroups;
 
 	*pp = NULL;
 
@@ -256,6 +259,14 @@ aggr_port_create(aggr_grp_t *grp, const datalink_id_t linkid, boolean_t force,
 	/* LACP related state */
 	port->lp_collector_enabled = B_FALSE;
 
+	/* Allocate the set of rx group handles. */
+	mac_perim_enter_by_mh(port->lp_mh, &mph);
+	num_rgroups = mac_get_num_rx_groups(port->lp_mh);
+	mac_perim_exit(mph);
+	port->lp_hwgh_count = num_rgroups;
+	port->lp_hwghs_size = sizeof (mac_group_handle_t) * num_rgroups;
+	port->lp_hwghs = kmem_zalloc(port->lp_hwghs_size, KM_SLEEP);
+
 	*pp = port;
 	return (0);
 
@@ -593,7 +604,7 @@ aggr_port_addmac(aggr_port_t *port, uint_t idx, const uint8_t *mac_addr)
 	int			err;
 
 	ASSERT(MAC_PERIM_HELD(port->lp_grp->lg_mh));
-	ASSERT3U(idx, <, MAX_GROUPS_PER_PORT);
+	ASSERT3U(idx, <, port->lp_grp->lg_rx_group_count);
 	mac_perim_enter_by_mh(port->lp_mh, &pmph);
 
 	/*
@@ -602,7 +613,7 @@ aggr_port_addmac(aggr_port_t *port, uint_t idx, const uint8_t *mac_addr)
 	 * let the aggr SW classify its traffic. This scenario happens
 	 * when mixing ports with a different number of HW groups.
 	 */
-	if (port->lp_hwghs[idx] == NULL)
+	if (idx >= port->lp_hwgh_count || port->lp_hwghs[idx] == NULL)
 		idx = 0;
 
 	/*
@@ -657,7 +668,7 @@ aggr_port_remmac(aggr_port_t *port, uint_t idx, const uint8_t *mac_addr)
 	mac_perim_handle_t	pmph;
 
 	ASSERT(MAC_PERIM_HELD(grp->lg_mh));
-	ASSERT3U(idx, <, MAX_GROUPS_PER_PORT);
+	ASSERT3U(idx, <, grp->lg_rx_group_count);
 	mac_perim_enter_by_mh(port->lp_mh, &pmph);
 
 	/*
@@ -684,7 +695,7 @@ aggr_port_remmac(aggr_port_t *port, uint_t idx, const uint8_t *mac_addr)
 			(void) aggr_port_promisc(port, B_FALSE);
 	} else {
 		/* See comment in aggr_port_addmac(). */
-		if (port->lp_hwghs[idx] == NULL)
+		if (idx >= port->lp_hwgh_count || port->lp_hwghs[idx] == NULL)
 			idx = 0;
 
 		ASSERT3P(port->lp_hwghs[idx], !=, NULL);
@@ -701,11 +712,11 @@ aggr_port_addvlan(aggr_port_t *port, uint_t idx, uint16_t vid)
 	int			err;
 
 	ASSERT(MAC_PERIM_HELD(port->lp_grp->lg_mh));
-	ASSERT3U(idx, <, MAX_GROUPS_PER_PORT);
+	ASSERT3U(idx, <, port->lp_grp->lg_rx_group_count);
 	mac_perim_enter_by_mh(port->lp_mh, &pmph);
 
 	/* See comment in aggr_port_addmac(). */
-	if (port->lp_hwghs[idx] == NULL)
+	if (idx >= port->lp_hwgh_count || port->lp_hwghs[idx] == NULL)
 		idx = 0;
 
 	/*
@@ -714,7 +725,7 @@ aggr_port_addvlan(aggr_port_t *port, uint_t idx, uint16_t vid)
 	 * implicitly allow tagged traffic to pass and there is
 	 * nothing to do.
 	 */
-	if (port->lp_hwghs[idx] == NULL)
+	if (idx >= port->lp_hwgh_count || port->lp_hwghs[idx] == NULL)
 		err = 0;
 	else
 		err = mac_hwgroup_addvlan(port->lp_hwghs[idx], vid);
@@ -730,14 +741,14 @@ aggr_port_remvlan(aggr_port_t *port, uint_t idx, uint16_t vid)
 	int			err;
 
 	ASSERT(MAC_PERIM_HELD(port->lp_grp->lg_mh));
-	ASSERT3U(idx, <, MAX_GROUPS_PER_PORT);
+	ASSERT3U(idx, <, port->lp_grp->lg_rx_group_count);
 	mac_perim_enter_by_mh(port->lp_mh, &pmph);
 
 	/* See comment in aggr_port_addmac(). */
-	if (port->lp_hwghs[idx] == NULL)
+	if (idx >= port->lp_hwgh_count || port->lp_hwghs[idx] == NULL)
 		idx = 0;
 
-	if (port->lp_hwghs[idx] == NULL)
+	if (idx >= port->lp_hwgh_count || port->lp_hwghs[idx] == NULL)
 		err = 0;
 	else
 		err = mac_hwgroup_remvlan(port->lp_hwghs[idx], vid);
diff --git a/usr/src/uts/common/sys/aggr_impl.h b/usr/src/uts/common/sys/aggr_impl.h
index de4162bc6112..edbfb2d68977 100644
--- a/usr/src/uts/common/sys/aggr_impl.h
+++ b/usr/src/uts/common/sys/aggr_impl.h
@@ -57,8 +57,6 @@ extern "C" {
  */
 #define	MAC_PSEUDO_RING_INUSE	0x01
 
-#define	MAX_GROUPS_PER_PORT	128
-
 /*
  * VLAN filters placed on the Rx pseudo group.
  */
@@ -160,7 +158,9 @@ typedef struct aggr_port_s {
 	 * Used by aggr to program HW classification for the pseudo
 	 * groups.
 	 */
-	mac_group_handle_t	lp_hwghs[MAX_GROUPS_PER_PORT];
+	size_t				lp_hwghs_size;
+	uint_t				lp_hwgh_count;
+	mac_group_handle_t	*lp_hwghs;
 
 	uint_t			lp_tx_ring_alloc;
 	uint_t			lp_tx_ring_cnt;
@@ -255,7 +255,8 @@ typedef struct aggr_grp_s {
 	boolean_t	lg_lacp_done;
 
 	uint_t			lg_rx_group_count;
-	aggr_pseudo_rx_group_t	lg_rx_groups[MAX_GROUPS_PER_PORT];
+	size_t			lg_rx_groups_size;
+	aggr_pseudo_rx_group_t	*lg_rx_groups;
 
 	aggr_pseudo_tx_group_t	lg_tx_group;