Fix outdated workspace nodeSelector documentation (#2690)

modules/administration-guide/pages/configuring-workspaces-nodeselector.adoc

@@ -10,11 +10,34 @@
 This section describes how to configure link:https://kubernetes.io/docs/concepts/scheduling-eviction/assign-pod-node/[`nodeSelector`] for Pods of {prod-short} workspaces.
 
 .Procedure
-
-{prod-short} uses the `CHE_WORKSPACE_POD_NODE__SELECTOR` environment variable to configure `nodeSelector`. This variable can contain a set of comma-separated `key=value` pairs to form the nodeSelector rule, or `NULL` to disable it.
-
+.. Using NodeSelector
++
+{prod-short} uses `CheCluster` Custom Resource to configure `nodeSelector`:
++
+[source,yaml]
+----
+spec:
+  devEnvironments:
+    nodeSelector:
+      key: value
+----
+This section must contain a set of `key=value` pairs for each link:https://kubernetes.io/docs/concepts/scheduling-eviction/assign-pod-node/#built-in-node-labels[node label] to form the link:https://kubernetes.io/docs/concepts/scheduling-eviction/assign-pod-node/#nodeselector[nodeSelector] rule.
+
+.. Using Taints and Tolerations
++
+This works in the opposite way to `nodeSelector`. Instead of specifying which nodes the Pod will be scheduled on, you specify which nodes the Pod cannot be scheduled on. For more information, see: link:https://kubernetes.io/docs/concepts/scheduling-eviction/taint-and-toleration[].
++
+{prod-short} uses `CheCluster` Custom Resource to configure `tolerations`:
++
+[source,yaml]
 ----
-CHE_WORKSPACE_POD_NODE__SELECTOR=disktype=ssd,cpu=xlarge,[key=value]
+spec:
+  devEnvironments:
+    tolerations:
+      - effect: NoSchedule
+        key: key
+        value: value
+        operator: Equal
 ----
 
 [IMPORTANT]
@@ -23,7 +46,7 @@ CHE_WORKSPACE_POD_NODE__SELECTOR=disktype=ssd,cpu=xlarge,[key=value]
 
 To avoid Pods and PVCs to be scheduled in different zones on large, multizone clusters, create an additional link:https://kubernetes.io/docs/concepts/storage/storage-classes/[`StorageClass`] object (pay attention to the `allowedTopologies` field), which will coordinate the PVC creation process.
 
-Pass the name of this newly created `StorageClass` to {prod-short} through the `+CHE_INFRA_KUBERNETES_PVC_STORAGE__CLASS__NAME+` environment variable. A default empty value of this variable instructs {prod-short} to use the cluster's default `StorageClass`.
+Pass the name of this newly created `StorageClass` to {prod-short} through the `CheCluster` Custom Resource. For more information, see: xref:configuring-storage-classes.adoc[].
 ====
 
 .Additional resources