diff --git a/nova/tests/unit/virt/libvirt/test_driver.py b/nova/tests/unit/virt/libvirt/test_driver.py
index fe93672de4b8..d9ee76e204d6 100644
--- a/nova/tests/unit/virt/libvirt/test_driver.py
+++ b/nova/tests/unit/virt/libvirt/test_driver.py
@@ -16157,6 +16157,14 @@ class LibvirtConnTestCase(test.NoDBTestCase,
             guest.domtype = ['kvm']
             caps.guests.append(guest)
 
+            # Include one that is not known to nova to make sure it
+            # does not trip us up.
+            guest = vconfig.LibvirtConfigGuest()
+            guest.ostype = 'hvm'
+            guest.arch = 'itanic'
+            guest.domtype = ['kvm']
+            caps.guests.append(guest)
+
             return caps
 
         self.stubs.Set(host.Host, "get_capabilities",
diff --git a/nova/virt/libvirt/driver.py b/nova/virt/libvirt/driver.py
index 378b210c2c5d..6fadbb9774f4 100644
--- a/nova/virt/libvirt/driver.py
+++ b/nova/virt/libvirt/driver.py
@@ -5861,11 +5861,17 @@ class LibvirtDriver(driver.ComputeDriver):
             for dt in g.domtype:
                 if dt != CONF.libvirt.virt_type:
                     continue
-                instance_cap = (
-                    fields.Architecture.canonicalize(g.arch),
-                    fields.HVType.canonicalize(dt),
-                    fields.VMMode.canonicalize(g.ostype))
-                instance_caps.append(instance_cap)
+                try:
+                    instance_cap = (
+                        fields.Architecture.canonicalize(g.arch),
+                        fields.HVType.canonicalize(dt),
+                        fields.VMMode.canonicalize(g.ostype))
+                    instance_caps.append(instance_cap)
+                except exception.InvalidArchitectureName:
+                    # NOTE(danms): Libvirt is exposing a guest arch that nova
+                    # does not even know about. Avoid aborting here and
+                    # continue to process the rest.
+                    pass
 
         return instance_caps