---
title: "Primary interface configuration"
description: "Reference for primary interface configuration parameters in the Calico Open Source VPP data plane."
product: "Calico Open Source"
version: "3.32 (latest)"
section: "Reference"
canonical_url: "https://docs.tigera.io/calico/latest/reference/vpp/uplink-configuration"
---

# Primary interface configuration

You can choose different ways to consume the host's primary interface with VPP, usually with a tradeoff between performance and simplicity of configuration. Here are the main supported configurations.

- `virtio` the interface is consumed with a native VPP driver. Performance is good and set up is simple, but only virtio interfaces are supported.
- `avf` we create a virtual function and consume it with a native VPP driver. Performance is good and setup simple, but only intel AVF interfaces are supported.
- `af_packet` the interface stays in Linux which passes packets to VPP. Performance is low, but it works out of the box with any interface.
- `af_xdp` packets are passed via eBPF. This requires a `>=5.4` kernel, but works out of the box with good performance.
- `dpdk` the interface is removed from Linux and consumed with the dpdk library. Performance and support are good, but setup can be complex.
- other native VPP drivers bring better performance than `dpdk` but require complex manual setup.

## General mechanics

The `calico-vpp-config` ConfigMap section of the manifest file contains the key `CALICOVPP_INTERFACES`, which is a dictionary with parameters specific to interfaces in Calico VPP:

```yaml
# Configures parameters for calicovpp agent and vpp manager
CALICOVPP_INTERFACES: |-
    {
      "maxPodIfSpec": {
        "rx": 10, "tx": 10, "rxqsz": 1024, "txqsz": 1024
      },
      "defaultPodIfSpec": {
        "rx": 1, "tx":1, "isl3": true
      },
      "vppHostTapSpec": {
        "rx": 1, "tx":1, "rxqsz": 1024, "txqsz": 1024, "isl3": false
      },
      "uplinkInterfaces": [
        {
          "interfaceName": "eth1",
          "vppDriver": "af_packet"
        }
      ]
    }
```

The field `uplinkInterfaces` contains a list of interfaces and their configuration, with the first element being the primary/main interface, and the rest (if any) being the secondary host interfaces. The way the primary interface gets configured is controlled by the `vppDriver` field in `uplinkInterfaces[0]`. Leaving the `vppDriver` field empty (or unspecified) will try all drivers (except `dpdk` which needs to be specified explicitly) supported in your setup, starting with the most performant. You'll still need to allocate hugepages if you want, for example, virtio to work.

> **SECONDARY:** `CALICOVPP_NATIVE_DRIVER` way of specifying the driver to use is still supported. Refer to **Legacy options** sub-section of [Getting Started](https://docs.tigera.io/calico/latest/getting-started/kubernetes/vpp/getting-started.md).

## Using the native Virtio driver

You can use this driver if your primary interface is virtio (`realpath /sys/bus/pci/devices/<PCI_ID>/driver` gives `.../virtio-net`)

- Ensure you have hugepages available on your system (`sysctl -w vm.nr_hugepages=512`)
- Ensure `vfio-pci` is loaded (`sudo modprobe vfio-pci`)
- For the primary interface, `uplinkInterfaces[0]`, set `vppDriver` to "virtio"
- Also ensure that your vpp config has no `dpdk` stanza and its plugin disabled

Optionally if you would like to set the number/size of **rx** queues, refer to **UplinkInterfaceSpec** sub-section of [Getting Started](https://docs.tigera.io/calico/latest/getting-started/kubernetes/vpp/getting-started.md).

## Using the native AVF driver

You can use this driver if your primary interface is supported by AVF (`realpath /sys/bus/pci/devices/<PCI_ID>/driver` gives `.../i40e`)

- Ensure `vfio-pci` is loaded (`sudo modprobe vfio-pci`)
- For the primary interface, `uplinkInterfaces[0]`, set `vppDriver` to "avf"
- Also ensure that your vpp config has no `dpdk` stanza and its plugin disabled

Optionally if you would like to set the number/size of **rx** queues, refer to **UplinkInterfaceSpec** sub-section of [Getting Started](https://docs.tigera.io/calico/latest/getting-started/kubernetes/vpp/getting-started.md).

## Using AF\_XDP

> **WARNING:** Ensure your kernel is at least `5.4` with `uname -r`

- For the primary interface, `uplinkInterfaces[0]`, set `vppDriver` to "af\_xdp"
- Also ensure that your vpp config has no `dpdk` stanza and its plugin disabled
- Finally `FELIX_XDPENABLED` should be set to `false` on the `calico-node` container otherwise felix will periodically cleanup the VPP configuration
  ```yaml
  ---
  kind: DaemonSet
  apiVersion: apps/v1
  metadata:
    name: calico-node
    namespace: kube-system
  spec:
    template:
      spec:
        containers:
          - name: calico-node
            env:
              - name: FELIX_XDPENABLED
                value: 'false'
  ```

With kustomize use `kubectl kustomize ./yaml/overlays/af-xdp | kubectl apply -f -`.

Optionally if you would like to set the number/size of **rx** queues or if you would like to customize whether we busy-poll the interface (`polling`), only use interrupts to wake us up (`interrupt`) or switch between both depending on the load (`adaptive`), refer to **UplinkInterfaceSpec** sub-section of [Getting Started](https://docs.tigera.io/calico/latest/getting-started/kubernetes/vpp/getting-started.md).

#### Side notes

- AF\_XDP won't start if you specify `buffers { buffers-per-numa }` to be too big (65536 should work)

## Using AF\_PACKET

- For the primary interface, `uplinkInterfaces[0]`, set `vppDriver` to "af\_packet"
- Also ensure that your vpp config has no `dpdk` stanza and the dpdk plugin is disabled

You can also use `kubectl kustomize ./yaml/overlays/af-packet | kubectl apply -f -`

## Using DPDK

- Ensure you have hugepages available on your system (`sysctl -w vm.nr_hugepages=512`)
- For the primary interface, `uplinkInterfaces[0]`, set `vppDriver` to "dpdk"

## Using native drivers with vpp's CLI

This is a rather advanced/experimental setup and we'll take the example of the AVF driver for this, using vpp cli, but any vpp driver can be used. This allows to efficiently support other interface types.

- For the primary interface, `uplinkInterfaces[0]`, set `vppDriver` to "none"
- Ensure that your vpp config has no `dpdk` stanza and the dpdk plugin is disabled
- Make sure the `exec /etc/vpp/startup.exec` entry is present in `unix { .. }`
  ```yaml
  CALICOVPP_CONFIG_TEMPLATE: |-
    unix {
      nodaemon
      full-coredump
      log /var/run/vpp/vpp.log
      cli-listen /var/run/vpp/cli.sock
      exec /etc/vpp/startup.exec
    }
    ...
    # removed dpdk { ... }
    ...
    plugins {
        plugin default { enable }
        plugin calico_plugin.so { enable }
        plugin dpdk_plugin.so { disable }
    }
  ```
- Update the `CALICOVPP_CONFIG_EXEC_TEMPLATE` environment variable to pass the interface creation cli command(s).
  ```yaml
  kind: DaemonSet
  apiVersion: apps/v1
  metadata:
    name: calico-vpp-node
    namespace: calico-vpp-dataplane
  spec:
    template:
      spec:
        containers:
          - name: vpp
            env:
              - name: CALICOVPP_CONFIG_EXEC_TEMPLATE
                value: 'create interface avf 0000:ab:cd.1 num-rx-queues 1'
  ```

In the specific case of the AVF driver, the PCI id must belong to a VF that can be created with the `avf.sh` [script](https://github.com/projectcalico/vpp-dataplane/blob/v3.32.0/test/scripts/utils/avf.sh). Different drivers will have different requirements.