longhorn: Run on dedicated nodes

I've created new worker nodes that are dedicated to running Longhorn
replicas.  These nodes are tainted with the
`node-role.kubernetes.io/longhorn` taint, so no regular pods will be
scheduled there by default.  Longhorn pods thus needs to be configured
to tolerate that taint, and to be scheduled on nodes with the
similarly-named label.

storage/longhorn-settings.yaml

@@ -3,4 +3,4 @@ kind: Setting
 metadata:
   name: taint-toleration
   namespace: longhorn-system
-value: du5t1n.me/machine=raspberrypi:NoExecute
+value: du5t1n.me/machine=raspberrypi:NoExecute;node-role.kubernetes.io/longhorn:NoSchedule

storage/longhorn.yaml

@@ -63,7 +63,7 @@ data:
     reclaimPolicy: "Delete"
     volumeBindingMode: Immediate
     parameters:
-      numberOfReplicas: "3"
+      numberOfReplicas: "2"
       staleReplicaTimeout: "30"
       fromBackup: ""
       fsType: "ext4"
@@ -3877,6 +3877,9 @@ spec:
       - key: du5t1n.me/machine
         operator: Exists
         effect: NoExecute
+      - key: node-role.kubernetes.io/longhorn
+        operator: Exists
+        effect: NoSchedule
       initContainers:
       - name: wait-longhorn-admission-webhook
         image: longhornio/longhorn-manager:v1.4.1
@@ -4017,9 +4020,15 @@ spec:
             value: "longhornio/csi-snapshotter:v5.0.1"
           - name: CSI_LIVENESS_PROBE_IMAGE
             value: "longhornio/livenessprobe:v2.8.0"
+      nodeSelector:
+        node-role.kubernetes.io/longhorn: ''
       serviceAccountName: longhorn-service-account
       securityContext:
         runAsUser: 0
+      tolerations:
+      - key: node-role.kubernetes.io/longhorn
+        operator: Exists
+        effect: NoSchedule
 ---
 # Source: longhorn/templates/deployment-recovery-backend.yaml
 apiVersion: apps/v1
@@ -4085,7 +4094,13 @@ spec:
           valueFrom:
             fieldRef:
               fieldPath: spec.nodeName
+      nodeSelector:
+        node-role.kubernetes.io/longhorn: ''
       serviceAccountName: longhorn-service-account
+      tolerations:
+      - key: node-role.kubernetes.io/longhorn
+        operator: Exists
+        effect: NoSchedule
 ---
 # Source: longhorn/templates/deployment-ui.yaml
 apiVersion: apps/v1
@@ -4099,7 +4114,7 @@ metadata:
   name: longhorn-ui
   namespace: longhorn-system
 spec:
-  replicas: 1
+  replicas: 2
   selector:
     matchLabels:
       app: longhorn-ui
@@ -4142,6 +4157,12 @@ spec:
             value: "http://longhorn-backend:9500"
           - name: LONGHORN_UI_PORT
             value: "8000"
+      nodeSelector:
+        node-role.kubernetes.io/longhorn: ''
+      tolerations:
+      - key: node-role.kubernetes.io/longhorn
+        operator: Exists
+        effect: NoSchedule
       volumes:
       - emptyDir: {}
         name: nginx-cache
@@ -4208,7 +4229,13 @@ spec:
           valueFrom:
             fieldRef:
               fieldPath: metadata.namespace
+      nodeSelector:
+        node-role.kubernetes.io/longhorn: ''
       serviceAccountName: longhorn-service-account
+      tolerations:
+      - key: node-role.kubernetes.io/longhorn
+        operator: Exists
+        effect: NoSchedule
 ---
 # Source: longhorn/templates/deployment-webhook.yaml
 apiVersion: apps/v1
@@ -4279,7 +4306,13 @@ spec:
           valueFrom:
             fieldRef:
               fieldPath: spec.nodeName
+      nodeSelector:
+        node-role.kubernetes.io/longhorn: ''
       serviceAccountName: longhorn-service-account
+      tolerations:
+      - key: node-role.kubernetes.io/longhorn
+        operator: Exists
+        effect: NoSchedule
 ---
 # Source: longhorn/templates/validate-psp-install.yaml
 #