diff --git a/installing/installing_openstack/installing-openstack-installer-custom.adoc b/installing/installing_openstack/installing-openstack-installer-custom.adoc
index 96c42086eaa1..118a3080fd53 100644
--- a/installing/installing_openstack/installing-openstack-installer-custom.adoc
+++ b/installing/installing_openstack/installing-openstack-installer-custom.adoc
@@ -29,6 +29,7 @@ include::modules/installation-osp-describing-cloud-parameters.adoc[leveloffset=+
 include::modules/installation-obtaining-installer.adoc[leveloffset=+1]
 include::modules/installation-initializing.adoc[leveloffset=+1]
 include::modules/installation-configuration-parameters.adoc[leveloffset=+1]
+include::modules/installation-osp-custom-subnet.adoc[leveloffset=+2]
 include::modules/installation-osp-config-yaml.adoc[leveloffset=+2]
 include::modules/ssh-agent-using.adoc[leveloffset=+1]
 include::modules/installation-osp-accessing-api.adoc[leveloffset=+1]
diff --git a/installing/installing_openstack/installing-openstack-installer-kuryr.adoc b/installing/installing_openstack/installing-openstack-installer-kuryr.adoc
index 2529ac7b7729..83ab0ee37b63 100644
--- a/installing/installing_openstack/installing-openstack-installer-kuryr.adoc
+++ b/installing/installing_openstack/installing-openstack-installer-kuryr.adoc
@@ -32,6 +32,7 @@ include::modules/installation-osp-describing-cloud-parameters.adoc[leveloffset=+
 include::modules/installation-obtaining-installer.adoc[leveloffset=+1]
 include::modules/installation-initializing.adoc[leveloffset=+1]
 include::modules/installation-configuration-parameters.adoc[leveloffset=+1]
+include::modules/installation-osp-custom-subnet.adoc[leveloffset=+2]
 include::modules/installation-osp-kuryr-config-yaml.adoc[leveloffset=+2]
 include::modules/ssh-agent-using.adoc[leveloffset=+1]
 include::modules/installation-osp-accessing-api.adoc[leveloffset=+1]
diff --git a/installing/installing_openstack/installing-openstack-user-kuryr.adoc b/installing/installing_openstack/installing-openstack-user-kuryr.adoc
index ea3ad1d01b48..6497d77913cc 100644
--- a/installing/installing_openstack/installing-openstack-user-kuryr.adoc
+++ b/installing/installing_openstack/installing-openstack-user-kuryr.adoc
@@ -43,6 +43,7 @@ include::modules/installation-osp-describing-cloud-parameters.adoc[leveloffset=+
 include::modules/installation-user-infra-generate.adoc[leveloffset=+1]
 include::modules/installation-initializing.adoc[leveloffset=+1]
 include::modules/installation-configuration-parameters.adoc[leveloffset=+1]
+include::modules/installation-osp-custom-subnet.adoc[leveloffset=+2]
 include::modules/installation-osp-kuryr-config-yaml.adoc[leveloffset=+2]
 include::modules/installation-osp-fixing-subnet.adoc[leveloffset=+2]
 include::modules/installation-osp-emptying-worker-pools.adoc[leveloffset=+2]
diff --git a/installing/installing_openstack/installing-openstack-user.adoc b/installing/installing_openstack/installing-openstack-user.adoc
index ca7e7efe1faf..f2440077b7fa 100644
--- a/installing/installing_openstack/installing-openstack-user.adoc
+++ b/installing/installing_openstack/installing-openstack-user.adoc
@@ -38,6 +38,7 @@ include::modules/installation-osp-describing-cloud-parameters.adoc[leveloffset=+
 include::modules/installation-user-infra-generate.adoc[leveloffset=+1]
 include::modules/installation-initializing.adoc[leveloffset=+1]
 include::modules/installation-configuration-parameters.adoc[leveloffset=+1]
+include::modules/installation-osp-custom-subnet.adoc[leveloffset=+2]
 include::modules/installation-osp-config-yaml.adoc[leveloffset=+2]
 include::modules/installation-osp-fixing-subnet.adoc[leveloffset=+2]
 include::modules/installation-osp-emptying-worker-pools.adoc[leveloffset=+2]
diff --git a/modules/installation-configuration-parameters.adoc b/modules/installation-configuration-parameters.adoc
index 1af0969db0b6..05783f204a25 100644
--- a/modules/installation-configuration-parameters.adoc
+++ b/modules/installation-configuration-parameters.adoc
@@ -283,10 +283,6 @@ ifdef::osp[]
 `clouds.yaml` file.
 |String, for example `MyCloud`.
 
-|`platform.openstack.externalDNS`
-|_Optional_. IP addresses for external DNS servers that cluster instances use for DNS resolution.
-|A list of IP addresses as strings, for example `["8.8.8.8", "192.168.1.12"]`.
-
 |`platform.openstack.externalNetwork`
 |The {rh-openstack} external network name to be used for installation.
 |String, for example `external`.
@@ -298,9 +294,19 @@ ifdef::osp[]
 |`platform.openstack.lbFloatingIP`
 |An existing floating IP address to associate with the load balancer API.
 |An IP address, for example `128.0.0.1`.
+|====
+
+.Optional {rh-openstack} parameters
+[cols=".^2m,.^3a,^3a,options="header"]
+|====
+|Parameter|Description|Values
+
+|`platform.openstack.externalDNS`
+|IP addresses for external DNS servers that cluster instances use for DNS resolution.
+|A list of IP addresses as strings, for example `["8.8.8.8", "192.168.1.12"]`.
 
 |`platform.openstack.defaultMachinePlatform`
-| _Optional_. The default machine pool platform configuration.
+|The default machine pool platform configuration.
 |
 [source,json]
 ----
@@ -312,6 +318,16 @@ ifdef::osp[]
    }
 }
 ----
+
+|`platform.openstack.machinesSubnet`
+|The UUID of a {rh-openstack} subnet that the cluster's nodes use. Nodes and VIP ports are created on this subnet.
+
+The first item in `networking.machineNetwork` must match the value of `machinesSubnet`.
+
+If you deploy to a custom subnet, you cannot specify an external DNS server to the {product-title} installer. Instead, link:https://access.redhat.com/documentation/en-us/red_hat_openstack_platform/16.0/html/command_line_interface_reference/subnet[add DNS to the subnet in {rh-openstack}].
+
+|A UUID as a string, for example `fa806b2f-ac49-4bce-b9db-124bc64209bf`.
+
 |====
 endif::osp[]
 
diff --git a/modules/installation-osp-custom-subnet.adoc b/modules/installation-osp-custom-subnet.adoc
new file mode 100644
index 000000000000..731c4ceb43c3
--- /dev/null
+++ b/modules/installation-osp-custom-subnet.adoc
@@ -0,0 +1,32 @@
+// Module included in the following assemblies:
+//
+
+// * installing/installing_openstack/installing-openstack-installer-custom.adoc
+// * installing/installing_openstack/installing-openstack-installer-kuryr.adoc
+// * installing/installing_openstack/installing-openstack-user.adoc
+// * installing/installing_openstack/installing-openstack-user-kuryr.adoc
+
+[id="installation-osp-custom-subnet_{context}"]
+= Custom subnets in {rh-openstack} deployments
+
+Optionally, you can deploy a cluster on a {rh-openstack-first} subnet of your choice. The subnet's GUID is passed as the value of `platform.openstack.machinesSubnet` in the `install-config.yaml` file.
+
+This subnet is used as the cluster's primary subnet; nodes and ports are created on it.
+
+Before you run the {product-title} installer with a custom subnet, verify that:
+
+* The target network and subnet are available.
+
+* DHCP is enabled on the target subnet.
+
+* You can provide installer credentials that have permission to create ports on the target network.
+
+* If your network configuration requires a router, it is created in {rh-openstack}. Some configurations rely on routers for floating IP address translation.
+
+* Your network configuration does not rely on a provider network. Provider networks are not supported.
+
+[NOTE]
+====
+By default, the API VIP takes x.x.x.5 and the Ingress VIP takes x.x.x.7 from your network's CIDR block. To override these default values,
+set values for `platform.openstack.apiVIP` and `platform.openstack.ingressVIP` that are outside of the DHCP allocation pool.
+====