support for Dynamic Resource Allocation doc update

Signed-off-by: Moshe Levi <moshele@nvidia.com>

docs/how-to-use.md

@@ -511,7 +511,7 @@ spec:
 EOF
 ```
 
-We can then create a pod which uses the `default-route` key in the JSON formatted `k8s.v1.cni.cncf.io/networks` annotation. 
+We can then create a pod which uses the `default-route` key in the JSON formatted `k8s.v1.cni.cncf.io/networks` annotation.
 
 ```
 cat <<EOF | kubectl create -f -
@@ -537,9 +537,9 @@ This will set `192.168.2.1` as the default route over the `net1` interface, such
 ```
 kubectl exec -it samplepod -- ip route
 
-default via 192.168.2.1 dev net1 
-10.244.0.0/24 dev eth0  proto kernel  scope link  src 10.244.0.169 
-10.244.0.0/16 via 10.244.0.1 dev eth0 
+default via 192.168.2.1 dev net1
+10.244.0.0/24 dev eth0  proto kernel  scope link  src 10.244.0.169
+10.244.0.0/16 via 10.244.0.1 dev eth0
 ```
 
 ## Entrypoint Parameters
@@ -634,3 +634,116 @@ Sometimes, you may wish to not have the entrypoint copy the binary file onto the
 If you wish to have auto configuration use the `readinessindicatorfile` in the configuration, you can use the `--readiness-indicator-file` to express which file should be used as the readiness indicator.
 
     --readiness-indicator-file=/path/to/file
+
+### Run pod with network annotation and Dynamic Resource Allocation driver
+
+Dynamic Resource Allocation is alternative mechanism to device plugin which allow to requests pod and container resources. The feature is alpha in k8s 1.27.
+
+The following sections describe how to use DRA with multus and Nvidia DRA driver. Other DRA networking driver vendors should follow similar concepts to make use of multus DRA support.
+
+#### Prerequisite
+
+1. Kubernetes 1.27
+2. Container Runtime with CDI support enabled
+3. Kubernetes runtime-config=resource.k8s.io/v1alpha2
+4. Kubernetes feature-gates=DynamicResourceAllocation=True,KubeletPodResourcesDynamicResources=true
+
+#### Install DRA driver
+
+The current example uses Nvidia DRA driver for networking. This DRA driver is not publicly available.
+
+#### Create dynamic resource class with nvidia network DRA driver
+
+The `ResourceClass` defines the resource pool of `sf-pool-1`.
+
+```
+# Execute following command at Kubernetes master
+cat <<EOF | kubectl create -f -
+apiVersion: resource.k8s.io/v1alpha2
+kind: ResourceClass
+metadata:
+  name: sf-pool-1
+driverName: net.resource.nvidia.com
+EOF
+```
+
+#### Create network attachment definition with resource name
+
+The `k8s.v1.cni.cncf.io/resourceName` should match the `ResourceClass` name defined in the section above.
+In this example it is `sf-pool-1`. Multus query the K8s PodResource API to fetch the `resourceClass` name and also
+query the NetworkAttachmentDefinition `k8s.v1.cni.cncf.io/resourceName`. If both has the same name multus send the
+CDI device name in the DeviceID argument.
+
+##### NetworkAttachmentDefinition for ovn-kubernetes example:
+
+Following command creates NetworkAttachmentDefinition. CNI config is in `config:` field.
+
+```
+# Execute following command at Kubernetes master
+cat <<EOF | kubectl create -f -
+apiVersion: "k8s.cni.cncf.io/v1"
+kind: NetworkAttachmentDefinition
+metadata:
+  name: default
+  annotations:
+    k8s.v1.cni.cncf.io/resourceName: sf-pool-1
+spec:
+  config: '{
+      "cniVersion": "0.4.0",
+      "dns": {},
+      "ipam": {},
+      "logFile": "/var/log/ovn-kubernetes/ovn-k8s-cni-overlay.log",
+      "logLevel": "4",
+      "logfile-maxage": 5,
+      "logfile-maxbackups": 5,
+      "logfile-maxsize": 100,
+      "name": "ovn-kubernetes",
+      "type": "ovn-k8s-cni-overlay"
+    }'
+EOF
+```
+
+#### Create DRA Resource Claim
+
+Following command creates `ResourceClaim` `sf` which request resource from  `ResourceClass` `sf-pool-1`.
+
+```
+# Execute following command at Kubernetes master
+cat <<EOF | kubectl create -f -
+apiVersion: resource.k8s.io/v1alpha2
+kind: ResourceClaim
+metadata:
+  namespace: default
+  name: sf
+spec:
+  spec:
+    resourceClassName: sf-pool-1
+EOF
+```
+
+#### Launch pod with DRA Resource Claim
+
+Following command Launch a Pod with primiry network `default` and `ResourceClaim` `sf`.
+
+```
+apiVersion: v1
+kind: Pod
+metadata:
+  namespace: default
+  name: test-sf-claim
+  annotations:
+    v1.multus-cni.io/default-network: default
+spec:
+  restartPolicy: Always
+  containers:
+  - name: with-resource
+    image: docker.io/library/ubuntu:22.04
+    command: ["/bin/sh", "-ec", "while :; do echo '.'; sleep 5 ; done"]
+    resources:
+      claims:
+      - name: resource
+  resourceClaims:
+  - name: resource
+    source:
+      resourceClaimName: sf
+```