Do not use hostnames to serialize upgrade of DNS servers.

move_fast_and_break_things.org

@@ -3,7 +3,7 @@
 I'll just leave this here...
 #+begin_src yaml
 #! /usr/bin/env ansible-playbook
-- hosts: OpenBSD:!gb-lon2.tlakh.xyz:!vultr.tlakh.xyz
+- hosts: OpenBSD:!dns
   gather_facts: False
   tasks:
     - name: run sysupgrade
@@ -13,8 +13,9 @@ I'll just leave this here...
       async: 3600
       poll: 0
 
-- hosts: gb-lon2.tlakh.xyz:!vultr.tlakh.xyz
+- hosts: dns:!ansible_orchestrator
   gather_facts: False
+  serial: 1
   tasks:
     - name: run sysupgrade -n
       ansible.builtin.command:
@@ -38,6 +39,7 @@ I'll just leave this here...
             delay: 10
           vars:
             ansible_connection: local
+
         - name: wait for DNS to come back.
           ansible.builtin.wait_for:
             state: started
@@ -48,7 +50,7 @@ I'll just leave this here...
             ansible_connection: local
       when: upgrade_pending.stat.exists
 
-- hosts: vultr.tlakh.xyz
+- hosts: ansible_orchestrator
   gather_facts: False
   tasks:
     - name: run sysupgrade