Keep Some Existing Nodes and Exclude Them from Optimization

In some scenarios, users may want to keep certain nodes:

Some nodes are on an annual or monthly subscription, and they have not yet expired. These nodes should be kept until their subscription ends.
Some nodes are Reserved Instances (RI) or Savings Plan (SP), and the contract has not yet expired. These should also be kept until their contract ends.

Reserved Instances (RI): Prepaid instances with significant discounts for a 1- or 3-year commitment to a specific instance type and region.
Savings Plan: A flexible commitment-based discount model that applies to various instance types and regions over 1 or 3 years.

By following the steps below, you can selectively optimize only a part of the nodes.

Install CloudPilot AI

Before proceeding, please install CloudPilot AI by following the instructions in the Quickstart guide. However, remember to only execute the first three steps.

Add Annotations to Nodes

Add annotation karpenter.sh/do-not-disrupt: "true" to the nodes you want to keep. For example:


$ kubectl get node
NAME                       STATUS   ROLES    AGE    VERSION
node-01.172.16.0.167       Ready    <none>   60m    v1.31.1-k8s.1
node-02.172.16.3.212       Ready    <none>   2m8s   v1.31.1-k8s.1
 
$ kubectl annotate node node-01.172.16.0.167 karpenter.sh/do-not-disrupt=true
node/node-01.172.16.0.167 annotated

Once you’ve annotated the nodes, go to the console, and you’ll see the annotated node will be kept:

Start Cluster Optimization

Now, click the Start Saving button. CloudPilot AI will begin optimizing only the nodes that are not annotated. In the end, you will see that only the un-annotated nodes are optimized.