TELCODOCS-1476 hub-side templating

modules/ztp-deploying-a-site.adoc

@@ -91,6 +91,34 @@ The `enable-crun-master.yaml` and `enable-crun-worker.yaml` CR files are in the
 For more information, see "Customizing extra installation manifests in the {ztp} pipeline".
 ====
 
+.. Optional: To reduce the number of policies for a deployment, you can use hub-side templates with a `PolicyGenTemplate`.
+You can use the `spec.clusters.siteConfigMap` section of the `SiteConfig` custom resource (CR) to specify per-site data to be used for hub-side templating.
+The following is an example use of the `data` field in `SiteConfig`:
++
+[source,yaml]
+----
+siteConfigMap:
+   name: site-example-sno <1>
+   namespace: ztp-pgs <2>
+   data:
+      sno-1-sriov-network-vlan-1: "140"
+      sno-1-sriov-network-vlan-2: "150"
+      updateConfigMapWithThisValue: "3"
+----
+<1> Specifies the name of the `ConfigMap` to be created. If unspecified, the default name is `ztp-site-<cluster_name>`. 
+<2> The default namesapce is `ztp-site`. For a successful integration with the `PolicyGenTemplate`, the `siteConfigMap.namespace` you specify must be the same as the namespace used by the `PolicyGenTemplate` resources.
++
+[IMPORTANT]
+====
+The `spec.clusters.siteConfigMap` section is available for `SiteConfig` CRs with `apiVersion: ran.openshift.io/v2` only. 
+Earlier versions do not support this function.
+====
++
+[NOTE]
+====
+As an alternative to populating the `siteConfigMap` section in the `SiteConfig` CR, you can store site-specific template data in the {ztp} repo, as `ConfigMap` CRs, and have them synced to the hub cluster.
+====
+
 . Add the `SiteConfig` CR to the `kustomization.yaml` file in the `generators` section, similar to the example shown in `out/argocd/example/siteconfig/kustomization.yaml`.
 
 . Commit the `SiteConfig` CR and associated `kustomization.yaml` changes in your Git repository and push the changes.

modules/ztp-the-policygentemplate.adoc

@@ -168,3 +168,15 @@ spec:
                                     domainNumber 24
                                     .....
 ----
+
+The following example uses hub-side templating to generate `PerformanceProfile` {rh-rhacm} policies for clusters that match the labels defined under `spec.bindingRules`.
+[source,yaml]
+----
+include::snippets/ztp_example-pgt-hub-side-templating.yaml[]
+----
+
+Using the `fromConfigMap` function, {rh-rhacm} selects the site-specific configuration for each cluster defined in the `PolicyGenTemplate`.
+This example generates policies for clusters that have the labels: 
+
+* 'group-du-sno-zone: "zone-1"'
+* 'hardware-type: "dell-poweredge-xr12"'

scalability_and_performance/ztp_far_edge/ztp-configuring-managed-clusters-policies.adoc

@@ -16,6 +16,7 @@ include::modules/ztp-pgt-config-best-practices.adoc[leveloffset=+1]
 .Additional resources
 
 * For recommendations about scaling clusters with {rh-rhacm}, see link:https://access.redhat.com/documentation/en-us/red_hat_advanced_cluster_management_for_kubernetes/2.6/html/install/installing#performance-and-scalability[Performance and scalability].
+* For information on working with templates, see link:https://access.redhat.com/documentation/en-us/red_hat_advanced_cluster_management_for_kubernetes/2.8/html-single/governance/index#template-processing[Template processing].
 
 [NOTE]
 ====

scalability_and_performance/ztp_far_edge/ztp-deploying-far-edge-sites.adoc

@@ -27,6 +27,8 @@ include::modules/ztp-deploying-a-site.adoc[leveloffset=+1]
 .Additional resources
 
 * xref:../../scalability_and_performance/ztp_far_edge/ztp-deploying-far-edge-sites.adoc#ztp-sno-siteconfig-config-reference_ztp-deploying-far-edge-sites[{sno-caps} SiteConfig CR installation reference]
+* For information on working with templates, see xref:../../scalability_and_performance/ztp_far_edge/ztp-advanced-policy-config.html#ztp-using-hub-cluster-templates_ztp-advanced-policy-config[Using hub templates in PolicyGenTemplate CRs].
+* For information on the `fromConfigmap` function, see link:https://access.redhat.com/documentation/en-us/red_hat_advanced_cluster_management_for_kubernetes/2.8/html-single/governance/index#fromConfigMap-func[fromConfigmap function].
 
 include::modules/ztp-sno-siteconfig-config-reference.adoc[leveloffset=+2]
 

snippets/ztp_example-pgt-hub-side-templating.yaml

@@ -0,0 +1,39 @@
+# For this PGT, we've considered an SNO managed cluster with the following labels:
+#   group-du-sno-zone: zone-1 
+#   hardware-type: dell-poweredge-xr12
+---
+apiVersion: ran.openshift.io/v1
+kind: PolicyGenTemplate
+metadata:
+  # The name will be used to generate the placementBinding and placementRule names as {name}-placementBinding and {name}-placementRule
+  name: "group-du-sno-zone-1"
+  namespace: "ztp-du-sno"
+spec:
+  bindingRules:
+    # These policies will correspond to all clusters with these labels
+    group-du-sno-zone: "zone-1"
+    hardware-type: "dell-poweredge-xr12"
+  mcp: "master"
+  sourceFiles:
+    # config-policy
+    ###
+    - fileName: PerformanceProfile.yaml # wave 10
+      policyName: "config-policy"
+      metadata:
+        name: openshift-node-performance-profile
+      spec:
+        additionalKernelArgs:
+        - rcupdate.rcu_normal_after_boot=0
+        - vfio_pci.enable_sriov=1
+        - vfio_pci.disable_idle_d3=1
+        - efi=runtime
+        cpu:
+          isolated: '{{hub fromConfigMap "" (printf "site-%s-configmap" .ManagedClusterName) (printf "%s-cpu-isolated" (index .ManagedClusterLabels "hardware-type")) hub}}'
+          reserved: '{{hub fromConfigMap "" (printf "site-%s-configmap" .ManagedClusterName)  (printf "%s-cpu-reserved" (index .ManagedClusterLabels "hardware-type")) hub}}'
+        hugepages:
+          defaultHugepagesSize: '{{hub fromConfigMap "" (printf "site-%s-configmap" .ManagedClusterName) (printf "%s-hugepages-default" (index .ManagedClusterLabels "hardware-type")) hub}}'
+          pages:
+            - size: '{{hub fromConfigMap "" (printf "site-%s-configmap" .ManagedClusterName) (printf "%s-hugepages-size" (index .ManagedClusterLabels "hardware-type")) hub}}'
+              count: '{{hub fromConfigMap "" (printf "site-%s-configmap" .ManagedClusterName) (printf "%s-hugepages-count" (index .ManagedClusterLabels "hardware-type")) | toInt hub}}'
+        realTimeKernel:
+          enabled: true