# Kubernetes clouds and Juju In Juju, all Kubernetes clouds behave fundamentally the same. ## Kubernetes in Juju Juju supports both traditional machine clouds as well as Kubernetes clouds. If you are familiar with Kubernetes, the following is a mapping between Kubernetes and Juju concepts: | Juju | Kubernetes | |----------------------------------------------------------------------------------------------------------|--------------------------------------------------------------------------------------------| | [model](https://documentation.ubuntu.com/juju/2.9/reference/model.md#model) | [namespace](https://kubernetes.io/docs/concepts/overview/working-with-objects/namespaces/) | | [machine](https://documentation.ubuntu.com/juju/2.9/reference/machine.md#machine); Juju does not manage this for Kubernetes | [node](https://kubernetes.io/docs/concepts/architecture/nodes/) | | [unit](https://documentation.ubuntu.com/juju/2.9/reference/unit.md#unit) | [pod](https://kubernetes.io/docs/concepts/workloads/pods/) | | process in a unit | container | | [application](https://documentation.ubuntu.com/juju/2.9/reference/application.md#application) | [service](https://kubernetes.io/docs/concepts/services-networking/service/) | ## Notes on `juju add-k8s` On Kubernetes clouds, both the cloud definition and the cloud credentials are added through `juju add-k8s`, which reads from your kubeconfig file. ### Authentication types #### `certificate` Attributes: - ClientCertificateData: the kubernetes certificate data (required) - Token: the kubernetes service account bearer token (required) - rbac-id: the unique ID key name of the rbac resources (optional) #### `clientcertificate` Attributes: - ClientCertificateData: the kubernetes certificate data (required) - ClientKeyData: the kubernetes certificate key (required) - rbac-id: the unique ID key name of the rbac resources (optional) #### `oauth2` Attributes: - Token: the kubernetes token (required) - rbac-id: the unique ID key name of the rbac resources (optional) #### `oauth2withcert` Attributes: - ClientCertificateData: the kubernetes certificate data (required) - ClientKeyData: the kubernetes private key data (required) - Token: the kubernetes token (required) #### `userpass` Attributes: - username: The username to authenticate with. (required) - password: The password for the specified username. (required) ## Cloud-specific model configuration keys ### `operator-storage` The storage class used to provision operator storage. | | | |---------------|--------| | type | string | | default value | “” | | immutable | true | | mandatory | false | ### `workload-storage` The preferred storage class used to provision workload storage. | | | |---------------|--------| | type | string | | default value | “” | | immutable | false | | mandatory | false | ## Supported constraints | [CONSTRAINT](https://documentation.ubuntu.com/juju/2.9/reference/constraint.md#constraint) | | |---------------------------------------------------------------------------------------------------|-----------------------------------------------| | conflicting: | `instance-type` vs. `[cores, cpu-power, mem]` | | supported? | | | - [allocate-public-ip](https://documentation.ubuntu.com/juju/2.9/reference/constraint.md#constraint-allocate-public-ip) | ✕ | | - [arch](https://documentation.ubuntu.com/juju/2.9/reference/constraint.md#constraint-arch) | ✕ | | - [container](https://documentation.ubuntu.com/juju/2.9/reference/constraint.md#constraint-container) | ✕ | | - [cores](https://documentation.ubuntu.com/juju/2.9/reference/constraint.md#constraint-cores) | ✕ | | - [cpu-power](https://documentation.ubuntu.com/juju/2.9/reference/constraint.md#constraint-cpu-power) | ✓ | | - [image-id](https://documentation.ubuntu.com/juju/2.9/reference/constraint.md#constraint-image-id) | ✕ | | - [instance-role](https://documentation.ubuntu.com/juju/2.9/reference/constraint.md#constraint-instance-role) | ✕ | | - [instance-type](https://documentation.ubuntu.com/juju/2.9/reference/constraint.md#constraint-instance-type) | ✕ | | - [mem](https://documentation.ubuntu.com/juju/2.9/reference/constraint.md#constraint-mem) | ✓ | | - [root-disk](https://documentation.ubuntu.com/juju/2.9/reference/constraint.md#constraint-root-disk) | ✕ | | - [root-disk-source](https://documentation.ubuntu.com/juju/2.9/reference/constraint.md#constraint-root-disk-source) | ✕ | | - [spaces](https://documentation.ubuntu.com/juju/2.9/reference/constraint.md#constraint-spaces) | ✕ | | - [tags](https://documentation.ubuntu.com/juju/2.9/reference/constraint.md#constraint-tags) | ✓
Used for affinity. | | - [virt-type](https://documentation.ubuntu.com/juju/2.9/reference/constraint.md#constraint-virt-type) | ✕ | | - [zones](https://documentation.ubuntu.com/juju/2.9/reference/constraint.md#constraint-zones) | ✕ | ## Placement directives Placement directives aren’t supported on Kubernetes clouds.