How to change the maxpod limit in RKE2 cluster

This document (000021093) is provided subject to the disclaimer at the end of this document.

Environment

Rancher 2.x
RKE2 cluster

Situation

The existing RKE2 cluster's pod limit has been exhausted and needs to be increased.

Resolution

Use the below arguments in the Rke2 configuration file /etc/rancher/rke2/config.yaml

kubelet-arg:
  - "max-pods=200"

Once the configurations are updated, you will need to restart the rke2-agent.service for the changes to apply.

If it's a downstream cluster managed through Rancher then, in the cluster configuration form, update the value under "Advanced" in kubelet args.

For rke2 clusters not managed by Rancher, this config is applied per-node

Status

Top Issue

Additional Information

When looking to change the max-pods for a node, make sure to take into account the number of IP addresses available from each nodes node-cidr, as this will limit the number of pods that can be scheduled on a node.

Example of JSON data for kubelet-arg max-pods.

{
  "node-label": [
    "cattle.io/os=linux",
    "rke.cattle.io/machine=46e7c4ec-9f13-4e54-a656-fab20689792a"
  ],
  "private-registry": "/etc/rancher/rke2/registries.yaml",
  "protect-kernel-defaults": false,
  "server": "https://xx.xxx.xx.xxx:9345",
  "token": "xxxxxxxxxxxxxx",
  "kubelet-arg": [
    "max-pods=120"
  ]
}

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