diff --git a/.automation b/.automation
index b00f285be..98e92aae8 160000
--- a/.automation
+++ b/.automation
@@ -1 +1 @@
-Subproject commit b00f285be240e34c643c4bd93a877e56587f71fa
+Subproject commit 98e92aae8460db84cd4bf9813e4ef1ba02c5e034
diff --git a/doc/source/configuration/vault.rst b/doc/source/configuration/vault.rst
index 87bdf8151..8c177570a 100644
--- a/doc/source/configuration/vault.rst
+++ b/doc/source/configuration/vault.rst
@@ -220,6 +220,8 @@ Enable the required TLS variables in kayobe and kolla
       # Whether TLS is enabled for the external API endpoints. Default is 'no'.
       kolla_enable_tls_external: yes
 
+   See :ref:`tempest-cacert` for information on adding CA certificates to the trust store when running Tempest.
+
 2. Set the following in kayobe-config/etc/kayobe/kolla.yml or if environments are being used etc/kayobe/environments/$KAYOBE_ENVIRONMENT/kolla.yml
 
    .. code-block::
diff --git a/doc/source/operations/tempest.rst b/doc/source/operations/tempest.rst
index c747b5377..e110e208f 100644
--- a/doc/source/operations/tempest.rst
+++ b/doc/source/operations/tempest.rst
@@ -251,6 +251,25 @@ ever contain one host. The seed is usually used as the tempest runner however
 it is also common to use the Ansible control host or an infrastructure VM. The
 main requirement of the host is that it can reach the OpenStack API.
 
+.. _tempest-cacert:
+
+Tempest CA certificate
+----------------------
+
+If your public OpenStack API uses TLS with a Certificate Authority (CA) that is
+not trusted by the Python CA trust store, it may be necessary to add a CA
+certificate to the trust store in the container that runs Tempest. This can be
+done by defining a ``tempest_cacert`` Ansible variable to a path containing the
+CA certificate. You may wish to use ``kayobe_config_path`` or
+``kayobe_env_config_path`` to be agnostic to the path where kayobe-config is
+mounted within the container. For example:
+
+.. code-block:: yaml
+   :caption: ``etc/kayobe/tempest.yml``
+
+   # Add the Vault CA certificate to the rally container when running tempest.
+   tempest_cacert: "{{ kayobe_env_config_path }}/kolla/certificates/ca/vault.crt"
+
 Running Tempest
 ===============
 
diff --git a/releasenotes/notes/tempest-cacert-33e2ae1cf0ba88cf.yaml b/releasenotes/notes/tempest-cacert-33e2ae1cf0ba88cf.yaml
new file mode 100644
index 000000000..83ddb8102
--- /dev/null
+++ b/releasenotes/notes/tempest-cacert-33e2ae1cf0ba88cf.yaml
@@ -0,0 +1,4 @@
+---
+features:
+  - |
+    Supports adding CA certificates to the Tempest container trust store.