Replace Cluster Nodes

This guide explains how to replace nodes in a Kubernetes cluster using KubeOps, which involves deleting an existing node and adding a new one through a YAML configuration file.

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Replace cluster nodes

This section describes how to replace cluster nodes in your cluster.

Direct replacement of nodes is not possible in KubeOps; however you can delete the node and add a new node to the cluster as shown in the following example.

Steps to replace a Kubernetes Node

Use the command delete on the admin node to delete the unwanted node from the cluster.

The command is:
```
lima delete -n <IP of your node> <name of your Cluster>
```
If you are deleting a node, then its data becomes inaccessible or erased.

Now create a new .yaml file with a configuration for the node as shown below

Example:

apiVersion: lima/nodeconfig/v1alpha1
clusterName: roottest
spec:
  masters: []
  workers:
  - host: 10.2.10.17  ## ip of the new node to be joined
    systemCpu: "200m"
    systemMemory: "200Mi"        
    user: root
    password: toor

Lastly use the command create nodes to create and join the new node.

The command is:
```
lima create nodes -f <node yaml file name>
```

Example 1

In the following example, we will replace a node with ip 10.2.10.15 from demoCluster to a new worker node with ip 10.2.10.17:

Delete node.
```
lima delete -n 10.2.10.15 demoCluster
```

create addNode.yaml for new worker node.

apiVersion: lima/nodeconfig/v1alpha1
clusterName: roottest
spec:
  masters: []
  workers:
  - host: 10.2.10.17
    systemCpu: "200m"
    systemMemory: "200Mi"
    user: root
    password: toor

Join the new node.
```
lima create nodes -f addNode.yaml
```

Example 2

If you are rejoining a master node, all other steps are the same except, you need to add the node configuration in the yaml file as shown in the example below:

apiVersion: lima/nodeconfig/v1alpha1
clusterName: roottest
spec:
  masters:
  - host: 10.2.10.17
    systemCpu: "200m"
    systemMemory: "200Mi"
    user: root
    password: toor
  workers: []