Update

Author: jab-rh

_topic_maps/_topic_map.yml

@@ -1728,6 +1728,8 @@ Topics:
     File: about-bgp-routing
   - Name: Configuring BGP routing
     File: configuring-bgp-routing
+  - Name: Migrating FRR-K8s custom resources
+    File: migrating-frr-k8s-resources
 ---
 Name: Storage
 Dir: storage

modules/nw-bgp-about.adoc

@@ -6,15 +6,7 @@
 [id="nw-bgp-about_{context}"]
 = About Border Gateway Protocol (BGP) routing
 
-With route advertisements enabled, {product-title} Networking supports the following features:
-
-- Importing routes from the provider network
-- Exporting routes into the provider network
-- Supporting multi-homing, link redundancy, and fast convergence for provider network gateways
-////
-https://github.com/openshift/openshift-docs/pull/85842/files#r1900917285
-- Improving throughput and reducing packet overhead
-////
+{product-title} supports BGP routing through FRRouting (FRR), a free, open source internet routing protocol suite for Linux and UNIX platforms. FRR-K8s is a Kubernetes based daemon set that exposes a subset of the FRR API in a Kubernetes-compliant manner. As a cluster administrator, you can use the FRRConfiguration custom resource (CR) to access FRR services.
 
 [id="supported-platforms_{context}"]
 == Supported platforms

modules/nw-bgp-frr-k8s-migration.adoc

@@ -0,0 +1,53 @@
+// Module included in the following assemblies:
+//
+// * networking/bgp_routing/migrating-frr-k8s-resources.adoc
+
+:_mod-docs-content-type: CONCEPT
+[id="nw-bgp-frr-k8s-migration_{context}"]
+= Migrating FRR-K8s resources
+
+You can migrate the FRR-K8s resources from the `openshift-frr-k8s` namespace to the `openshift-ovn-kubernetes` namespace.
+
+.Prerequisites
+
+* Install the OpenShift CLI (`oc`).
+* Log in to the cluster with a user with `cluster-admin` privileges.
+
+.Procedure
+
+When upgrading from an earlier version of {product-title} with the Metal LB Operator deployed, you must manually migrate your custom frr-k8s configurations from the `metallb-system` namespace to the `openshift-frr-k8s` namespace. To move these CRs, enter the following commands:
+
+. To create the `openshift-frr-k8s` namespace, enter the following command:
++
+[source,terminal]
+----
+$ oc create namespace openshift-frr-k8s
+----
+
+. To automate the migration, create a `migrate.sh` with the following content:
++
+[source,bash]
+----
+#!/bin/bash
+OLD_NAMESPACE="metallb-system"
+NEW_NAMESPACE="openshift-frr-k8s"
+FILTER_OUT="metallb-"
+oc get frrconfigurations.frrk8s.metallb.io -n "${OLD_NAMESPACE}" -o json |\
+  jq -r '.items[] | select(.metadata.name | test("'"${FILTER_OUT}"'") | not)' |\
+  jq -r '.metadata.namespace = "'"${NEW_NAMESPACE}"'"' |\
+  oc create -f -
+----
+
+. To execute the migration, run the following command:
++
+[source,terminal]
+----
+$ bash migrate.sh
+----
+
+. To confirm that the migration succeeded, run the following command:
++
+[source,terminal]
+----
+$ oc get frrconfigurations.frrk8s.metallb.io -n openshift-frr-k8s
+----

modules/nw-bgp-routing-config.adoc

@@ -35,7 +35,7 @@ $ oc patch network.operator cluster -p '{
 ----
 
 [id="disabling-bgp-routing-support_{context}"]
-== Disabling Border Gateway Protocol (BGP) routing support
+== Disabling BGP routing support
 
 As a cluster administrator, you can disable BGP routing support for your cluster.
 

networking/bgp_routing/about-bgp-routing.adoc

@@ -8,9 +8,7 @@ toc::[]
 
 This feature provides native Border Gateway Protocol (BGP) routing capabilities for the cluster.
 
-////
-Additionally, this feature must be enabled to use the RouteAdvertisements feature of the OVN-Kubernetes network plugin.
-////
+If you have any FRR-K8s custom resources that you created in the `metallb-system` namespace, you must migrate them to the `openshift-frr-k8s` namespace. For more information, see xref:../../networking/bgp_routing/migrating-frr-k8s-resources.adoc#migrating-frr-k8s-resources[Migrating FRR-K8s resources].
 
 include::modules/nw-bgp-about.adoc[leveloffset=+1]
 include::modules/nw-metallb-frr-k8s-configuration-crd.adoc[leveloffset=+1]

networking/bgp_routing/configuring-bgp-routing.adoc

@@ -8,8 +8,4 @@ toc::[]
 
 As a cluster administrator, you can configure OVN-Kubernetes Border Gateway Protocol (BGP) routing support for your cluster.
 
-////
-If you want to use route advertisements, you must enable BGP routing support. For more information, see xref!../../networking/route_advertisements/about-route-advertisements.adoc#about-route-advertisements[About route advertisements].
-////
-
 include::modules/nw-bgp-routing-config.adoc[leveloffset=+1]

networking/bgp_routing/migrating-frr-k8s-resources.adoc

@@ -0,0 +1,11 @@
+:_mod-docs-content-type: ASSEMBLY
+[id="migrating-frr-k8s-resources"]
+= Migrating FRR-K8s resources
+include::_attributes/common-attributes.adoc[]
+:context: migrating-frr-k8s-resources
+
+toc::[]
+
+All user-created FRR-K8s custom resources (CRs) in the `metallb-system` namespace under {product-title} 4.17 and earlier releases must be  migrated to the `openshift-frr-k8s` namespace. As a cluster administrator, complete the steps in this procedure to migrate your FRR-K8s custom resources.
+
+include::modules/nw-bgp-frr-k8s-migration.adoc[leveloffset=+1]