diff --git a/_data/reference.yml b/_data/reference.yml index e2439cc78b..a11214565a 100644 --- a/_data/reference.yml +++ b/_data/reference.yml @@ -226,6 +226,8 @@ toc: path: /docs/user-guide/replicasets/ - title: Pet Sets path: /docs/user-guide/petset/ + - title: Network Policies + path: /docs/user-guide/networkpolicies/ - title: Kubernetes Design Docs section: diff --git a/docs/user-guide/networkpolicies.md b/docs/user-guide/networkpolicies.md new file mode 100644 index 0000000000..e550657df6 --- /dev/null +++ b/docs/user-guide/networkpolicies.md @@ -0,0 +1,80 @@ +--- +--- + +* TOC +{:toc} + +A network policy is a specification of how selections of pods are allowed to communicate with each other and other network endpoints. + +`NetworkPolicy` resources use labels to select pods and define whitelist rules which allow traffic to the selected pods in addition to what is allowed by the isolation policy for a given namespace. + +## Prerequisites + +You must enable the `extensions/v1beta/networkpolicies` runtime config in your apiserver to enable this resource. + +You must also be using a networking solution which supports `NetworkPolicy` - simply creating the +resource without a controller to implement it will have no effect. + +## Configuring Namespace Isolation Policy + +Isolation can be configured on a per-namespace basis. Once isolation is configured on a namespace it will be applied to all pods in that namespace. Currently, only isolation policy on inbound traffic (ingress) can be defined. + +The following ingress isolation types being supported: + +- `DefaultDeny`: Pods in the namespace will be inaccessible from any source except the pod's local node. + +Ingress isolation can be enabled using an annotation on the Namespace. + +```yaml +kind: Namespace +apiVersion: v1 +metadata: + annotations: + net.beta.kubernetes.io/network-policy: | + { + "ingress": { + "isolation": "DefaultDeny" + } + } +``` + +To configure the annotation via `kubectl`: + +```shell{% raw %} +kubectl annotate ns "net.beta.kubernetes.io/networkpolicy={\"ingress\": {\"isolation\": \"DefaultDeny\"}}" +{% endraw %}``` + +## The `NetworkPolicy` Resource + +See the [api-reference](/docs/api-reference/extensions/v1beta1/definitions/#_v1beta1_networkpolicy) for a full definition of the resource. + +A minimal `NetworkPolicy` might look like this: + +```yaml +apiVersion: extensions/v1beta1 +kind: NetworkPolicy +metadata: + name: test-network-policy +spec: + podSelector: + matchLabels: + role: db + ingress: + - from: + podSelector: + matchLabels: + role: frontend + ports: + - protocol: tcp + port: 6379 +``` + +*POSTing this to the API server will have no effect unless your chosen networking solution supports network policy.* + +__Mandatory Fields__: As with all other Kubernetes config, a `NetworkPolicy` needs `apiVersion`, `kind`, and `metadata` fields. For general information about working with config files, see [here](/docs/user-guide/simple-yaml), [here](/docs/user-guide/configuring-containers), and [here](/docs/user-guide/working-with-resources). + +__spec__: `NetworkPolicy` [spec](https://github.com/kubernetes/kubernetes/tree/{{page.githubbranch}}/docs/devel/api-conventions.md#spec-and-status) has all the information needed to define a network isolation policy in the deployed controller. + +__podSelector__: Each `NetworkPolicy` includes a `podSelector` which selects the grouping of pods to which the `ingress` rules in the policy apply. + +__ingress__: Each `NetworkPolicy` includes a list of whitelist `ingress` rules. Each rule allows traffic which matches both the `from` and `ports` sections.