diff --git a/dev/tenks-deploy-config-compute.yml b/dev/tenks-deploy-config-compute.yml
index d73ae9800..6fc77adfe 100644
--- a/dev/tenks-deploy-config-compute.yml
+++ b/dev/tenks-deploy-config-compute.yml
@@ -38,6 +38,10 @@ deploy_ramdisk: ipa.initramfs
 # container. Tenks will install libvirt client packages.
 libvirt_host_install_daemon: false
 
+# Nested virtualisation is not working well in CI currently. Force the use of
+# QEMU.
+libvirt_vm_engine: "qemu"
+
 # QEMU may not be installed on the host, so set the path and avoid
 # autodetection.
 libvirt_vm_emulator: "/usr/libexec/qemu-kvm"
diff --git a/playbooks/kayobe-overcloud-base/pre.yml b/playbooks/kayobe-overcloud-base/pre.yml
index 0fa834231..3f03d8620 100644
--- a/playbooks/kayobe-overcloud-base/pre.yml
+++ b/playbooks/kayobe-overcloud-base/pre.yml
@@ -3,12 +3,6 @@
   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
diff --git a/playbooks/kayobe-overcloud-upgrade-base/pre.yml b/playbooks/kayobe-overcloud-upgrade-base/pre.yml
index bec74e650..cefbe5df2 100644
--- a/playbooks/kayobe-overcloud-upgrade-base/pre.yml
+++ b/playbooks/kayobe-overcloud-upgrade-base/pre.yml
@@ -1,12 +1,6 @@
 ---
 - 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/overrides.yml.j2 b/playbooks/kayobe-seed-vm-base/overrides.yml.j2
index cb7594011..4cbd700f6 100644
--- a/playbooks/kayobe-seed-vm-base/overrides.yml.j2
+++ b/playbooks/kayobe-seed-vm-base/overrides.yml.j2
@@ -18,6 +18,10 @@ pip_upper_constraints_file: "/tmp/upper-constraints.txt"
 # enabled. Don't fail if it's disabled.
 libvirt_host_require_vt: false
 
+# Nested virtualisation is not working well in CI currently. Force the use of
+# QEMU.
+libvirt_vm_engine: "qemu"
+
 # Use the CI infra's PyPI mirror.
 pip_local_mirror: true
 pip_index_url: "http://{{ zuul_site_mirror_fqdn }}/pypi/simple"
diff --git a/playbooks/kayobe-seed-vm-base/pre.yml b/playbooks/kayobe-seed-vm-base/pre.yml
index db722a6e7..85635fa53 100644
--- a/playbooks/kayobe-seed-vm-base/pre.yml
+++ b/playbooks/kayobe-seed-vm-base/pre.yml
@@ -3,12 +3,6 @@
   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