diff --git a/playbooks/kayobe-overcloud-base/ironic.conf b/playbooks/kayobe-overcloud-base/ironic.conf
new file mode 100644
index 000000000..45f848825
--- /dev/null
+++ b/playbooks/kayobe-overcloud-base/ironic.conf
@@ -0,0 +1,2 @@
+[DEFAULT]
+minimum_required_memory = 256
diff --git a/playbooks/kayobe-overcloud-base/pre.yml b/playbooks/kayobe-overcloud-base/pre.yml
index 38ca53d2a..0fa834231 100644
--- a/playbooks/kayobe-overcloud-base/pre.yml
+++ b/playbooks/kayobe-overcloud-base/pre.yml
@@ -3,6 +3,12 @@
   environment:
     KAYOBE_CONFIG_SOURCE_PATH: "{{ kayobe_config_src_dir }}"
   tasks:
+    # FIXME(mgoddard): work out what's going wrong here.
+    - name: Fail if running on Vexxhost infra
+      fail:
+        msg: Baremetal tests fail on vexxhost - roll the dice again
+      when: "'vexxhost' in ansible_hostname"
+
     # NOTE(mgoddard): Use the name zz-overrides.yml to ensure this takes
     # precedence over the standard config files.
     - name: Ensure kayobe-config override config file exists
@@ -16,6 +22,17 @@
         dest: "{{ kayobe_config_src_dir }}/etc/kayobe/kolla/globals.yml"
       when: tls_enabled
 
+    - name: Ensure kolla custom config dir exists
+      file:
+        path: "{{ kayobe_config_src_dir }}/etc/kayobe/kolla/config"
+        state: directory
+
+    # TODO(mgoddard): Remove this when it has been added to kayobe-config-dev.
+    - name: Ensure ironic.conf override config file exists
+      copy:
+        src: ironic.conf
+        dest: "{{ kayobe_config_src_dir }}/etc/kayobe/kolla/config/ironic.conf"
+
     # NOTE(mgoddard): The kayobe dev config by default expects a bridge -
     # breth1 - to exist with an IP address of 192.168.33.3.
     - name: Ensure all-in-one network bridge interface exists
diff --git a/playbooks/kayobe-overcloud-upgrade-base/pre.yml b/playbooks/kayobe-overcloud-upgrade-base/pre.yml
index cefbe5df2..bec74e650 100644
--- a/playbooks/kayobe-overcloud-upgrade-base/pre.yml
+++ b/playbooks/kayobe-overcloud-upgrade-base/pre.yml
@@ -1,6 +1,12 @@
 ---
 - hosts: primary
   tasks:
+    # FIXME(mgoddard): work out what's going wrong here.
+    - name: Fail if running on Vexxhost infra
+      fail:
+        msg: Baremetal tests fail on vexxhost - roll the dice again
+      when: "'vexxhost' in ansible_hostname"
+
     # NOTE(mgoddard): Use the name zz-overrides.yml to ensure this takes
     # precedence over the standard config files.
     - name: Ensure kayobe-config override config file exists
diff --git a/playbooks/kayobe-seed-vm-base/pre.yml b/playbooks/kayobe-seed-vm-base/pre.yml
index 85635fa53..db722a6e7 100644
--- a/playbooks/kayobe-seed-vm-base/pre.yml
+++ b/playbooks/kayobe-seed-vm-base/pre.yml
@@ -3,6 +3,12 @@
   environment:
     KAYOBE_CONFIG_SOURCE_PATH: "{{ kayobe_config_src_dir }}"
   tasks:
+    # FIXME(mgoddard): work out what's going wrong here.
+    - name: Fail if running on Vexxhost infra
+      fail:
+        msg: Seed VM tests fail on vexxhost - roll the dice again
+      when: "'vexxhost' in ansible_hostname"
+
     # NOTE(mgoddard): Use the name zz-overrides.yml to ensure this takes
     # precedence over the standard config files.
     - name: Ensure kayobe-config override config file exists
diff --git a/zuul.d/jobs.yaml b/zuul.d/jobs.yaml
index c7b9bfe53..0655af26f 100644
--- a/zuul.d/jobs.yaml
+++ b/zuul.d/jobs.yaml
@@ -117,9 +117,6 @@
     pre-run: playbooks/kayobe-overcloud-upgrade-base/pre.yml
     run: playbooks/kayobe-overcloud-upgrade-base/run.yml
     timeout: 9000
-    # Use fewer attempts for upgrades, since pre.yml includes deployment of the
-    # previous release which takes a considerable amount of time.
-    attempts: 3
 
 - job:
     name: kayobe-overcloud-upgrade-centos8
@@ -169,9 +166,6 @@
     pre-run: playbooks/kayobe-seed-upgrade-base/pre.yml
     run: playbooks/kayobe-seed-upgrade-base/run.yml
     timeout: 5400
-    # Use fewer attempts for upgrades, since pre.yml includes deployment of the
-    # previous release which takes a considerable amount of time.
-    attempts: 3
 
 - job:
     name: kayobe-seed-upgrade-centos8