Editing Cluster:Compute nodes (section)

== Targeting a specific node ==

Targeting a specific node can be done in two different ways, either selecting a node name directly, or requiring certain labels on the node.
See table above for node names and associated labels. 
See the [https://kubernetes.io/docs/concepts/scheduling-eviction/assign-pod-node/ Kubernetes API documentation on how to assign pods to nodes], or refer to the following examples, which are probably self-explaining.


=== Selecting a node name ===

Example: GPU-enabled pod which runs only on the node "belial". Note that Belial is a more powerful system, so it is protected by a taint, see table above. Thus, you also have to tolerate the respective taint so that the pod can actually be scheduled on Belial, which is explained below.

<syntaxhighlight>
apiVersion: v1
kind: Pod
metadata:
  name: gpu-pod
spec:
  nodeSelector:
    kubernetes.io/hostname: belial
  containers:
  - name: gpu-container
    image: nvcr.io/nvidia/tensorflow:20.09-tf2-py3
    command: ["sleep", "1d"]
    resources:
      requests:
        cpu: 1
        nvidia.com/gpu: 1
        memory: 10Gi
      limits:
        cpu: 1
        nvidia.com/gpu: 1
        memory: 10Gi
   # more specs (volumes etc.)
</syntaxhighlight>

=== Requiring a certain label on the node ===

Example: GPU-enabled pod which requires compute capability of at least sm-75:

<syntaxhighlight>
apiVersion: v1
kind: Pod
metadata:
  name: gpu-pod
spec:
  nodeSelector:
    compute-capability-atleast-sm75: true
    # note: if a node has e.g. the label "compute-capability-sm80", it also has the
    # corresponding "atleast"-label for all lower or equal compute capabilities. Same holds for "gpumem".
  containers:
  - name: gpu-container
    image: nvcr.io/nvidia/tensorflow:20.09-tf2-py3
    command: ["sleep", "1d"]
    resources:
      requests:
        cpu: 1
        nvidia.com/gpu: 1
        memory: 10Gi
      limits:
        cpu: 1
        nvidia.com/gpu: 1
        memory: 10Gi
   # more specs (volumes etc.)
</syntaxhighlight>