update: fix undefined error when no mgr group is declared

if mgr group isn't defined in inventory, that task will fail with
undefined error.

Signed-off-by: Guillaume Abrioux <gabrioux@redhat.com>
(cherry picked from commit c1e4529b0e44329f561fc46ec96bd081cdd6d38c)

diff --git a/infrastructure-playbooks/rolling_update.yml b/infrastructure-playbooks/rolling_update.yml
index 0ec4ccf201e838a2486c38ece5d2ded0c9a62c83..5b6449e3b75597a64bb03257ab83e7c4afdd1a29 100644 (file)
--- a/infrastructure-playbooks/rolling_update.yml
+++ b/infrastructure-playbooks/rolling_update.yml
@@ -172,8 +172,8 @@
         name: ceph-mgr@{{ ansible_hostname }}
         masked: yes
       when:
-        - inventory_hostname in groups[mgr_group_name]
-          or groups[mgr_group_name] | length == 0
+        - inventory_hostname in groups[mgr_group_name] | default([])
+          or groups[mgr_group_name] | default([]) | length == 0
 
     - import_role:
         name: ceph-handler