docs: instructions for uninstallation and operator usage

Describe NFD deployment via the operator.

Add minimal documentation for uninnstalling NFD. Add instructions and
template spec for running "nfd-master --prune".  Also modify the RBAC
rules in nfd-master spec template to make it possible doing --prune
(allow nfd-master to list nodes in the cluster).

docs/get-started/deployment-and-usage.md

@@ -25,7 +25,35 @@ sort: 3
 
 ### Operator
 
-*WORK IN PROGRESS...*
+Deployment using the
+[Node Feature Discovery Operator][nfd-operator]
+is recommended to be done via
+[operatorhub.io](https://operatorhub.io/operator/nfd-operator).
+
+1. You need to have
+   [OLM][OLM]
+   installed. If you don't, take a look at the
+   [latest release](https://github.com/operator-framework/operator-lifecycle-manager/releases/latest)
+   for detailed instructions.
+1. Install the operator:
+```bash
+kubectl create -f https://operatorhub.io/install/nfd-operator.yaml
+```
+1. Create NodeFeatureDiscovery resource (in `nfd` namespace here):
+```bash
+cat << EOF | kubectl apply -f -
+apiVersion: v1
+kind: Namespace
+metadata:
+  name: nfd
+---
+apiVersion: nfd.kubernetes.io/v1alpha1
+kind: NodeFeatureDiscovery
+metadata:
+  name: my-nfd-deployment
+  namespace: nfd
+EOF
+```
 
 ### Deployment Templates
 
@@ -220,4 +248,50 @@ For more details on targeting nodes, see
 
 ## Uninstallation
 
-*WORK IN PROGRESS...*
+### Operator Was Used for Deployment
+
+If you followed the deployment instructions above you can simply do:
+
+```bash
+kubectl -n nfd delete NodeFeatureDiscovery my-nfd-deployment
+```
+
+Optionally, you can also remove the namespace:
+
+```bash
+kubectl delete ns nfd
+```
+
+See the [node-feature-discovery-operator][nfd-operator] and [OLM][OLM] project
+documentation for instructions for uninstalling the operator and operator
+lifecycle manager, respectively.
+
+### Manual
+
+```bash
+NFD_NS=node-feature-discovery
+kubectl -n $NFD_NS delete ds nfd-worker
+kubectl -n $NFD_NS delete deploy nfd-master
+kubectl -n $NFD_NS delete svc nfd-master
+kubectl -n $NFD_NS delete sa nfd-master
+kubectl delete clusterrole nfd-master
+kubectl delete clusterrolebinding nfd-master
+```
+
+### Removing Feature Labels
+
+NFD-Master has a special `--prune` command line flag for removing all
+nfd-related node labels, annotations and extended resources from the cluster.
+
+```bash
+kubectl apply -f https://raw.githubusercontent.com/kubernetes-sigs/node-feature-discovery/master/nfd-prune.yaml.template
+kubectl -n node-feature-discovery wait job.batch/nfd-prune --for=condition=complete && \
+    kubectl -n node-feature-discovery delete job/nfd-prune
+```
+
+**NOTE:** You must run prune before removing the RBAC rules (serviceaccount,
+clusterrole and clusterrolebinding).
+
+<!-- Links -->
+[nfd-operator]: https://github.com/kubernetes-sigs/node-feature-discovery-operator
+[OLM]: https://github.com/operator-framework/operator-lifecycle-manager

nfd-master.yaml.template

@@ -25,6 +25,8 @@ rules:
   - get
   - patch
   - update
+  # List only needed for --prune
+  - list
 ---
 apiVersion: rbac.authorization.k8s.io/v1
 kind: ClusterRoleBinding

nfd-prune.yaml.template

@@ -0,0 +1,43 @@
+apiVersion: batch/v1
+kind: Job
+metadata:
+  name: nfd-prune
+  namespace: node-feature-discovery
+  labels:
+    app: nfe-prune
+spec:
+  completions: 1
+  template:
+    metadata:
+      labels:
+        app: nfd-prune
+    spec:
+      serviceAccount: nfd-master
+      affinity:
+        nodeAffinity:
+          preferredDuringSchedulingIgnoredDuringExecution:
+            - weight: 1
+              preference:
+                matchExpressions:
+                  - key: "node-role.kubernetes.io/master"
+                    operator: In
+                    values: [""]
+      tolerations:
+        - key: "node-role.kubernetes.io/master"
+          operator: "Equal"
+          value: ""
+          effect: "NoSchedule"
+      containers:
+        - image: gcr.io/k8s-staging-nfd/node-feature-discovery:master
+          name: nfd-master
+          securityContext:
+            allowPrivilegeEscalation: false
+            capabilities:
+              drop: ["ALL"]
+            readOnlyRootFilesystem: true
+            runAsNonRoot: true
+          command:
+            - "nfd-master"
+          args:
+            - "--prune"
+      restartPolicy: Never