diff --git a/opal/mca/hwloc/base/base.h b/opal/mca/hwloc/base/base.h
index 845e9e1e7f..45ab2e771d 100644
--- a/opal/mca/hwloc/base/base.h
+++ b/opal/mca/hwloc/base/base.h
@@ -139,6 +139,11 @@ OPAL_DECLSPEC int opal_hwloc_base_filter_cpus(hwloc_topology_t topo);
  */
 OPAL_DECLSPEC int opal_hwloc_base_get_topology(void);
 
+/**
+ * Set the hwloc topology to that from the given topo file
+ */
+OPAL_DECLSPEC int opal_hwloc_base_set_topology(char *topofile);
+
 /**
  * Free the hwloc topology.
  */
diff --git a/opal/mca/hwloc/base/hwloc_base_util.c b/opal/mca/hwloc/base/hwloc_base_util.c
index 7aeb92ab8f..6c77aca4f2 100644
--- a/opal/mca/hwloc/base/hwloc_base_util.c
+++ b/opal/mca/hwloc/base/hwloc_base_util.c
@@ -231,6 +231,87 @@ int opal_hwloc_base_get_topology(void)
     return rc;
 }
 
+int opal_hwloc_base_set_topology(char *topofile)
+{
+    hwloc_obj_t obj;
+    unsigned j, k;
+    struct hwloc_topology_support *support;
+    int rc;
+
+     OPAL_OUTPUT_VERBOSE((5, opal_hwloc_base_framework.framework_output,
+                         "hwloc:base:set_topology"));
+
+   if (NULL != opal_hwloc_topology) {
+        hwloc_topology_destroy(opal_hwloc_topology);
+    }
+    if (0 != hwloc_topology_init(&opal_hwloc_topology)) {
+        return OPAL_ERR_NOT_SUPPORTED;
+    }
+    if (0 != hwloc_topology_set_xml(opal_hwloc_topology, topofile)) {
+        hwloc_topology_destroy(opal_hwloc_topology);
+        return OPAL_ERR_NOT_SUPPORTED;
+    }
+    /* since we are loading this from an external source, we have to
+     * explicitly set a flag so hwloc sets things up correctly
+     */
+    if (0 != hwloc_topology_set_flags(opal_hwloc_topology,
+                                      (HWLOC_TOPOLOGY_FLAG_IS_THISSYSTEM |
+                                       HWLOC_TOPOLOGY_FLAG_WHOLE_SYSTEM |
+                                       HWLOC_TOPOLOGY_FLAG_IO_DEVICES))) {
+        hwloc_topology_destroy(opal_hwloc_topology);
+        return OPAL_ERR_NOT_SUPPORTED;
+    }
+    if (0 != hwloc_topology_load(opal_hwloc_topology)) {
+        hwloc_topology_destroy(opal_hwloc_topology);
+        return OPAL_ERR_NOT_SUPPORTED;
+    }
+    /* remove the hostname from the topology. Unfortunately, hwloc
+     * decided to add the source hostname to the "topology", thus
+     * rendering it unusable as a pure topological description. So
+     * we remove that information here.
+     */
+    obj = hwloc_get_root_obj(opal_hwloc_topology);
+    for (k=0; k < obj->infos_count; k++) {
+        if (NULL == obj->infos[k].name ||
+            NULL == obj->infos[k].value) {
+            continue;
+        }
+        if (0 == strncmp(obj->infos[k].name, "HostName", strlen("HostName"))) {
+            free(obj->infos[k].name);
+            free(obj->infos[k].value);
+            /* left justify the array */
+            for (j=k; j < obj->infos_count-1; j++) {
+                obj->infos[j] = obj->infos[j+1];
+            }
+            obj->infos[obj->infos_count-1].name = NULL;
+            obj->infos[obj->infos_count-1].value = NULL;
+            obj->infos_count--;
+            break;
+        }
+    }
+    /* unfortunately, hwloc does not include support info in its
+     * xml output :-(( We default to assuming it is present as
+     * systems that use this option are likely to provide
+     * binding support
+     */
+    support = (struct hwloc_topology_support*)hwloc_topology_get_support(opal_hwloc_topology);
+    support->cpubind->set_thisproc_cpubind = true;
+    support->membind->set_thisproc_membind = true;
+
+    /* filter the cpus thru any default cpu set */
+    rc = opal_hwloc_base_filter_cpus(opal_hwloc_topology);
+    if (OPAL_SUCCESS != rc) {
+        return rc;
+    }
+
+    /* fill opal_cache_line_size global with the smallest L1 cache
+       line size */
+    fill_cache_line_size();
+
+    /* all done */
+    return OPAL_SUCCESS;
+}
+
 static void free_object(hwloc_obj_t obj)
 {
     opal_hwloc_obj_data_t *data;
diff --git a/orte/mca/rmaps/base/help-orte-rmaps-base.txt b/orte/mca/rmaps/base/help-orte-rmaps-base.txt
index c1604ca239..1451c0c260 100644
--- a/orte/mca/rmaps/base/help-orte-rmaps-base.txt
+++ b/orte/mca/rmaps/base/help-orte-rmaps-base.txt
@@ -204,3 +204,14 @@ No objects of the specified type were found on at least one node:
   Node: %s
 
 The map cannot be done as specified.
+#
+[topo-file]
+A topology file was given for the compute nodes, but
+we were unable to correctly process it. Common errors
+include incorrectly specifying the path to the file,
+or the file being generated in a way that is incompatible
+with the version of hwloc being used by OMPI.
+
+  File: %s
+
+Please correct the problem and try again.
diff --git a/orte/mca/rmaps/base/rmaps_base_frame.c b/orte/mca/rmaps/base/rmaps_base_frame.c
index 7dce0f1cc7..0994404b11 100644
--- a/orte/mca/rmaps/base/rmaps_base_frame.c
+++ b/orte/mca/rmaps/base/rmaps_base_frame.c
@@ -33,6 +33,7 @@
 
 #include "orte/runtime/orte_globals.h"
 #include "orte/util/show_help.h"
+#include "orte/mca/errmgr/errmgr.h"
 
 #include "orte/mca/rmaps/base/rmaps_private.h"
 #include "orte/mca/rmaps/base/base.h"
@@ -65,6 +66,7 @@ static bool rmaps_base_no_oversubscribe = false;
 static bool rmaps_base_oversubscribe = false;
 static bool rmaps_base_display_devel_map = false;
 static bool rmaps_base_display_diffable_map = false;
+static char *rmaps_base_topo_file = NULL;
 
 static int orte_rmaps_base_register(mca_base_register_flag_t flags)
 {
@@ -202,6 +204,13 @@ static int orte_rmaps_base_register(mca_base_register_flag_t flags)
                                  OPAL_INFO_LVL_9,
                                  MCA_BASE_VAR_SCOPE_READONLY, &rmaps_base_display_diffable_map);
 
+    rmaps_base_topo_file = NULL;
+    (void) mca_base_var_register("orte", "rmaps", "base", "topology",
+                                 "hwloc topology file (xml format) describing the topology of the compute nodes [default: none]",
+                                 MCA_BASE_VAR_TYPE_STRING, NULL, 0, 0, OPAL_INFO_LVL_9,
+                                 MCA_BASE_VAR_SCOPE_READONLY, &rmaps_base_topo_file);
+
+
     return ORTE_SUCCESS;
 }
 
@@ -237,6 +246,18 @@ static int orte_rmaps_base_open(mca_base_open_flag_t flags)
     orte_rmaps_base.mapping = 0;
     orte_rmaps_base.ranking = 0;
 
+    /* if a topology file was given, then set our topology
+     * from it. Even though our actual topology may differ,
+     * mpirun only needs to see the compute node topology
+     * for mapping purposes
+     */
+    if (NULL != rmaps_base_topo_file) {
+        if (OPAL_SUCCESS != (rc = opal_hwloc_base_set_topology(rmaps_base_topo_file))) {
+            orte_show_help("help-orte-rmaps-base.txt", "topo-file", true, rmaps_base_topo_file);
+            return ORTE_ERR_SILENT;
+        }
+    }
+
     if (NULL == rmaps_base_mapping_policy) {
         ORTE_SET_MAPPING_POLICY(orte_rmaps_base.mapping, ORTE_MAPPING_BYSLOT);
         ORTE_UNSET_MAPPING_DIRECTIVE(orte_rmaps_base.mapping, ORTE_MAPPING_GIVEN);