Upgrade component-cilium to v4

Notable changes

Breaking changes

The Helm value ipam.operator.clusterPoolIPv4PodCIDRList is changed to [10.0.0.0/8] in the component defaults to match the Helm chart default value
The Helm value ipam.operator.clusterPoolIPv4MaskSize is changed to 24 in the component defaults to match the Helm chart default value
The Helm value endpointRoutes.enabled is changed to false in the component defaults to match the Helm chart default value

We keep explicit defaults for these Helm values. This ensures that any potential changes in the Helm chart defaults don’t impact existing clusters; in particular potential changes to the Pod CIDR values.

Other changes

OpenShift-specific values for Helm values cni.binPath and cni.confPath have been moved from component defaults to an OpenShift-specific Helm values overlay applied by the component.

Preserving the old defaults globally for a Project Syn environment

Prerequisites

Access to your Project Syn environment’s global defaults repository
Knowledge of how to upgrade a component globally in your environment
Knowledge of how to trigger catalog compilations / rollouts globally in your environment

Steps

Add the following configuration in a suitable file in your Project Syn global defaults repository

parameters:
  cilium:
    cilium_helm_values:
      endpointRoutes:
        enabled: true
      ipam: (1)
        operator:
          clusterPoolIPv4MaskSize: 23
          ~clusterPoolIPv4PodCIDRList: (2)
            - 10.128.0.0/14

1	We strongly recommend ensuring that you don’t modify the `ipam.operator` configurations for existing clusters. If you do change these configurations, you’ll most likely have to delete all existing pods to restore connectivity.
2	We use `~clusterPoolIPv4PodCIDRList` to override the parameter so that the list entry that’s added in the component defaults is dropped.

If you add this configuration in a low priority class in your global defaults, you can omit any sections that you’re customizing already in a higher priority class.

Commit and push the changes in the global defaults repository
Update the component through your usual mechanisms.
Trigger cluster compilations through your usual mechanisms.

Preserving the old defaults for an individual cluster or tenant

Prerequisites

Push access to the cluster’s tenant repository
Working Commodore installation

Steps

Compile the cluster catalog for the cluster that you want to update
```
CLUSTER_ID=<c-the-cluster-1234> (1)
```
1 Adjust with the cluster’s ID
```
commodore catalog compile $CLUSTER_ID
```

Update the cluster’s or tenant’s configuration with the old defaults and update the component

parameters:
  components:
    cilium:
      version: v4.0.0 (1)
  cilium:
    cilium_helm_values:
      endpointRoutes:
        enabled: true
      ipam: (2)
        operator:
          clusterPoolIPv4MaskSize: 23
          ~clusterPoolIPv4PodCIDRList: (3)
            - 10.128.0.0/14

1	Check the component’s GitHub releases for the latest v4 version. We always recommend updating to recent patch versions of components.
2	We strongly recommend ensuring that you don’t modify the `ipam.operator` configurations for existing clusters. If you do change these configurations, you’ll most likely have to delete all existing pods to restore connectivity.
3	We use `~clusterPoolIPv4PodCIDRList` to override the parameter so that the list entry that’s added in the component defaults is dropped.

Omit any fields that you’re configuring already through your Project Syn hierarchy.

Commit and push the changes in the tenant repository
Compile the cluster and verify that there’s no unwanted changes in the resulting diff
```
commodore catalog compile $CLUSTER_ID --push --interactive
```