Network Policy Resource (NetworkPolicy)

A network policy resource (NetworkPolicy) represents an ordered set of rules which are applied to a collection of endpoints that match a label selector.

NetworkPolicy is a namespaced resource. NetworkPolicy in a specific namespace only applies to workload endpoint resources in that namespace. Two resources are in the same namespace if the namespace value is set the same on both. See global network policy resource for non-namespaced network policy.

NetworkPolicy resources can be used to define network connectivity rules between groups of Calico endpoints and host endpoints, and take precedence over profile resources if any are defined.

For calicoctl commands that specify a resource type on the CLI, the following aliases are supported (all case insensitive): networkpolicy, networkpolicies, policy, np, policies, pol, pols.

Sample YAML

This sample policy allows TCP traffic from frontend endpoints to port 6379 on database endpoints.

apiVersion: projectcalico.org/v3
kind: NetworkPolicy
metadata:
  name: allow-tcp-6379
  namespace: production
spec:
  selector: role == 'database'
  types:
  - Ingress
  - Egress
  ingress:
  - action: Allow
    protocol: TCP
    source:
      selector: role == 'frontend'
    destination:
      ports:
      - 6379
  egress:
  - action: Allow

Definition

Metadata

Spec

* If types has no value, Calico defaults as follows.

Ingress Rules Present	Egress Rules Present	Types value
No	No	ingress
Yes	No	ingress
No	Yes	egress
Yes	Yes	ingress, egress

Rule

An action of Pass will skip over the remaining policies and jump to the first profile assigned to the endpoint, applying the policy configured in the profile; if there are no Profiles configured for the endpoint the default applied action is Deny.

ICMP

EntityRule

Selector

A label selector is an expression which either matches or does not match a resource based on its labels.

Calico label selectors support a number of syntactic primitives. Each of the following primitive expressions can be combined using the logical operator &&.

Ports

Calico supports the following syntaxes for expressing ports.

An individual numeric port may be specified as a YAML/JSON integer. A port range or named port must be represented as as a string. For example, this would be a valid list of ports:

ports: [8080, "1234:5678", "named-port"]

Named ports

Using a named port in an EntityRule, instead of a numeric port, gives a layer of indirection, allowing for the named port to map to different numeric values for each endpoint.

For example, suppose you have multiple HTTP servers running as workloads; some exposing their HTTP port on port 80 and others on port 8080. In each workload, you could create a named port called http-port that maps to the correct local port. Then, in a rule, you could refer to the name http-port instead of writing a different rule for each type of server.

NOTE: Since each named port may refer to many endpoints (and Calico has to expand a named port into a set of endpoint/port combinations), using a named port is considerably more expensive in terms of CPU than using a simple numeric port. We recommend that they are used sparingly, only where the extra indirection is required.

Supported operations