Red Hat OpenShift Container Platform

Configuration for a VLAN secondary network

The VLAN CNI plugin JSON configuration object describes the configuration parameters for the VLAN, vlan, CNI plugin. The following table details these parameters:

Field Type Description

Field	Type	Description
`cniVersion`	`string`	The CNI specification version. A minimum version of `0.3.1` is required.
`name`	`string`	The mandatory, unique identifier assigned to this CNI network attachment definition. It is used by the container runtime to select the correct network configuration and serves as the key for persistent resource state management, such as IP address allocations.
`type`	`string`	The name of the CNI plugin to configure: `vlan`.
`master`	`string`	The Ethernet interface to associate with the network attachment. If a `master` is not specified, the interface for the default network route is used.
`vlanId`	`integer`	Set the ID of the `vlan`.
`ipam`	`object`	The configuration object for the IPAM CNI plugin. The plugin manages IP address assignment for the attachment definition.
`mtu`	`integer`	Optional: Set the maximum transmission unit (MTU) to the specified value. The default value is automatically set by the kernel.
`dns`	`integer`	Optional: DNS information to return. For example, a priority-ordered list of DNS nameservers.
`linkInContainer`	`boolean`	Optional: Specifies whether the `master` interface is in the container network namespace or the main network namespace. Set the value to `true` to request the use of a container namespace `master` interface.

cniVersion

string

The CNI specification version. A minimum version of 0.3.1 is required.

name

string

The mandatory, unique identifier assigned to this CNI network attachment definition. It is used by the container runtime to select the correct network configuration and serves as the key for persistent resource state management, such as IP address allocations.

type

string

The name of the CNI plugin to configure: vlan.

master

string

The Ethernet interface to associate with the network attachment. If a master is not specified, the interface for the default network route is used.

vlanId

integer

Set the ID of the vlan.

ipam

object

The configuration object for the IPAM CNI plugin. The plugin manages IP address assignment for the attachment definition.

mtu

integer

Optional: Set the maximum transmission unit (MTU) to the specified value. The default value is automatically set by the kernel.

dns

integer

Optional: DNS information to return. For example, a priority-ordered list of DNS nameservers.

linkInContainer

boolean

Optional: Specifies whether the master interface is in the container network namespace or the main network namespace. Set the value to true to request the use of a container namespace master interface.

A NetworkAttachmentDefinition custom resource definition (CRD) with a vlan configuration can be used only on a single pod in a node because the CNI plugin cannot create multiple vlan subinterfaces with the same vlanId on the same master interface.

VLAN configuration example

The following example demonstrates a vlan configuration with a secondary network that is named vlan-net:

{
  "name": "vlan-net",
  "cniVersion": "0.3.1",
  "type": "vlan",
  "master": "eth0",
  "mtu": 1500,
  "vlanId": 5,
  "linkInContainer": false,
  "ipam": {
      "type": "host-local",
      "subnet": "10.1.1.0/24"
  },
  "dns": {
      "nameservers": [ "10.1.1.1", "8.8.8.8" ]
  }
}

ipam.type.host-local: Allocates IPv4 and IPv6 IP addresses from a specified set of address ranges. IPAM plugin stores the IP addresses locally on the host filesystem so that the addresses remain unique to the host.