diff --git a/ansible/roles/nova/tasks/discover_computes.yml b/ansible/roles/nova/tasks/discover_computes.yml
index 647bd5d59c..37d4ed0c97 100644
--- a/ansible/roles/nova/tasks/discover_computes.yml
+++ b/ansible/roles/nova/tasks/discover_computes.yml
@@ -1,5 +1,44 @@
 ---
-- name: Waiting for nova-compute service up
+# We need to wait for all expected compute services to register before running
+# cells v2 host discovery. This includes virtualised compute services and
+# ironic compute services.
+# Work with --limit by including only hosts in ansible_play_batch.
+- name: Build a list of expected compute service hosts
+  vars:
+    # For virt, use ansible_nodename rather than inventory_hostname, since this
+    # is similar to what nova uses internally as its default for the
+    # [DEFAULT] host config option.
+    virt_compute_service_hosts: >-
+      {{ groups['compute'] |
+         intersect(ansible_play_batch) |
+         map('extract', hostvars, 'ansible_nodename') |
+         list }}
+    # For ironic, use {{ansible_hostname}}-ironic since this is what we
+    # configure for [DEFAULT] host in nova.conf.
+    ironic_compute_service_hosts: >-
+      {{ (groups['nova-compute-ironic'] |
+          intersect(ansible_play_batch) |
+          map('extract', hostvars, 'ansible_hostname') |
+          map('regex_replace', '^(.*)$', '\1-ironic') |
+          list)
+         if enable_ironic | bool else [] }}
+  set_fact:
+    expected_compute_service_hosts: "{{ virt_compute_service_hosts + ironic_compute_service_hosts }}"
+  run_once: True
+  delegate_to: "{{ groups['nova-api'][0] }}"
+
+- name: Waiting for nova-compute services to register themselves
+  vars:
+    # A list containing the 'Host' field of compute services that have
+    # registered themselves.  Don't exclude compute services that are disabled
+    # since these could have been explicitly disabled by the operator. While we
+    # could exclude services that are down, the nova-manage cell_v2
+    # discover_hosts does not do this so let's not block on it here.
+    found_compute_service_hosts: >-
+      {{ nova_compute_services.stdout |
+         from_json |
+         map(attribute='Host') |
+         list }}
   become: true
   command: >
     docker exec kolla_toolbox openstack
@@ -12,7 +51,7 @@
     --os-password {{ keystone_admin_password }}
     --os-user-domain-name {{ openstack_auth.domain_name }}
     --os-region-name {{ openstack_region_name }}
-    compute service list -f json --service nova-compute
+    compute service list --format json --column Host --service nova-compute
   register: nova_compute_services
   changed_when: false
   run_once: True
@@ -21,7 +60,7 @@
   delay: 10
   until:
     - nova_compute_services is success
-    - nova_compute_services.stdout | from_json | length != 0
+    - found_compute_service_hosts is superset(expected_compute_service_hosts)
 
 # TODO(yoctozepto): no need to do --by-service if ironic not used
 - name: Discover nova hosts