Add guide for high performance multicast

modules/nw-configuring-high-performance-multicast-with-sriov.adoc

@@ -0,0 +1,100 @@
+// Module included in the following assemblies:
+//
+// * networking/multiple-networks/configuring-sr-iov.adoc
+
+= Configuring performance multicast
+
+Openshift SDN supports multicast between Pods on the default network. This is best used for low-bandwidth coordination or service discovery, and not a high-bandwidth solution. For applications of streaming media, such as IPTV and
+multipoint videoconferencing, you can utilize SR-IOV to provide near-native 
+performance.
+
+When using additional SR-IOV interfaces for multicast:
+
+* Multicast packages must be sent or received by a Pod through the additional SR-IOV
+interface.
+* The physical network which connects the SR-IOV interfaces decides the
+multicast routing and topology, which is not controlled by Openshift.
+
+= Using an SR-IOV interface for multicast
+
+The follow procedure creates an example SR-IOV interface for multicast.
+
+.Prerequisites
+
+* Install the OpenShift Command-line Interface (CLI), commonly known as `oc`.
+* You must log in to the cluster with a user that has the `cluster-admin` role.
+
+.Procedure
+. Create a SriovNetworkNodePolicy CR
+
++
+[source,yaml]
+----
+apiVersion: sriovnetwork.openshift.io/v1
+kind: SriovNetworkNodePolicy
+metadata:
+  name: policy-example
+  namespace: openshift-sriov-network-operator
+spec:
+  resourceName: example
+  nodeSelector:
+    feature.node.kubernetes.io/network-sriov.capable: "true"
+  numVfs: 4
+  nicSelector:
+    vendor: "8086"
+    pfName: ['ens803f0']
+    rootDevices: ['0000:86:00.0']
+----
+
+. Create a SriovNetwork CR
++
+[source,yaml]
+----
+apiVersion: sriovnetwork.openshift.io/v1
+kind: SriovNetwork
+metadata:
+  name: net-example
+  namespace: openshift-sriov-network-operator
+spec:
+  networkNamespace: default
+  ipam: |
+    {
+      "type": "host-local", <1>
+      "subnet": "10.56.217.0/24",
+      "rangeStart": "10.56.217.171",
+      "rangeEnd": "10.56.217.181",
+      "routes": [
+        {"dst": "224.0.0.0/5"},
+        {"dst": "232.0.0.0/5"}
+      ],
+      "gateway": "10.56.217.1"
+    } 
+  resourceName: example
+----
+<1> Make sure to provision the following default routes through your DHCP server
+224.0.0.0/5, 232.0.0.0/5, if you choose to use DHCP as IPAM. This is to override
+the static multicast route set by Openshift-SDN.
+
+. User can now create a Pod with multicast application
++
+[source,yaml]
+----
+apiVersion: v1
+kind: Pod
+metadata:
+  name: testpmd
+  namespace: default
+  annotations:
+    k8s.v1.cni.cncf.io/networks: nic1
+spec:
+  containers:
+  - name: example 
+    image: rhel7:latest
+    securityContext:
+      capabilities:
+        add: ["NET_ADMIN"] <1>
+    command: [ "sleep", "infinity"]
+----
+<1> The NET_ADMIN capability is only required if your application needs to 
+assign the multicast IP address to the SR-IOV interface. Otherwise, it can be
+omitted.

networking/multiple-networks/configuring-sr-iov.adoc

@@ -125,3 +125,5 @@ include::modules/nw-multus-add-pod.adoc[leveloffset=+1]
 include::modules/nw-sriov-add-pod-runtimeconfig.adoc[leveloffset=+1]
 
 include::modules/nw-sriov-topology-manager.adoc[leveloffset=+1]
+
+include::modules/nw-configuring-high-performance-multicast-with-sriov.adoc[leveloffset=+1]