Primary interface configuration

6 MINUTE READ

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 main interface configuration is controlled by a variable named CALICOVPP_NATIVE_DRIVER that is passed to the vpp container. You can edit the .yaml file as follows or use the overlays provided in ./yaml/overlays/*.

By default, leaving CALICOVPP_NATIVE_DRIVER empty (or unspecified) will try all drivers supported in your setup, starting with the most performant. You’ll still need to allocate hugepages if you want e.g. Virtio to work.

kind: DaemonSet
apiVersion: apps/v1
metadata:
  name: calico-vpp-node
  namespace: calico-vpp-dataplane
spec:
  template:
    spec:
      containers:
        - name: vpp
          env:
            - name: CALICOVPP_NATIVE_DRIVER
              value: "af_packet"

For most deployments (except for DPDK) you should ensure that the vpp configuration stanza has DPDK disabled

vpp_config_template: |-
    ...
    # removed dpdk { ... }
    ...
    plugins {
        plugin default { enable }
        plugin calico_plugin.so { enable }
        plugin dpdk_plugin.so { disable }
    }

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=256)

  • Ensure vfio-pci is loaded (sudo modprobe vfio-pci)

  • Pass CALICOVPP_NATIVE_DRIVER = virtio to the vpp container
  • Also ensure that your vpp config has no dpdk stanza and its plugin disabled
  • Optionally CALICOVPP_RX_QUEUES controls the number of queues used, CALICOVPP_RING_SIZE their size

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)

  • Pass CALICOVPP_NATIVE_DRIVER = avf to the vpp container
  • Also ensure that your vpp config has no dpdk stanza and its plugin disabled
  • Optionally CALICOVPP_RX_QUEUES controls the number of queues used, CALICOVPP_RING_SIZE their size

Using AF_XDP

Caution: Ensure your kernel is at least 5.4 with uname -r

  • Pass CALICOVPP_NATIVE_DRIVER = af_xdp to the vpp container
  • Also ensure that your vpp config has no dpdk stanza and its plugin disabled
  • Optionally CALICOVPP_RX_QUEUES controls the number of queues used, CALICOVPP_RING_SIZE their size
  • CALICOVPP_RX_MODE controls whether we busy-poll the interface (polling), only use interrupts to wake us up (interrupt) or switch between both depending on the load (adaptive)
  • Finally FELIX_XDPENABLED should be set to false on the calico-node container otherwise felix will periodically cleanup the VPP configuration 
    kind: DaemonSet
apiVersion: apps/v1
metadata:
name: calico-vpp-node
namespace: calico-vpp-dataplane
spec:
template:
  spec:
    containers:
      - name: vpp
        env:
          - name: CALICOVPP_NATIVE_DRIVER
            value: "af_xdp"
          - name: CALICOVPP_RING_SIZE
            value: "1024"
          - name: CALICOVPP_RX_QUEUES
            value: "1"
          - name: CALICOVPP_RX_MODE
            value: "polling"
---
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 -

Side nodes

  • AF_XDP won’t start if you specify buffers { buffers-per-numa } to be too big (65536 should work)

Using AF_PACKET

  • Pass CALICOVPP_NATIVE_DRIVER = af_packet to the vpp container
  • 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

With available hugepages

  • Ensure you have hugepages available on your system (sysctl -w vm.nr_hugepages=256)
  • Pass CALICOVPP_NATIVE_DRIVER = none to the vpp container
  • The vpp config in the calico-config ConfigMap should look like the following, __PCI_DEVICE_ID__ will be automatically populated with the PCI ID of CALICOVPP_INTERFACE at startup.
  • CALICOVPP_RX_QUEUES and CALICOVPP_RING_SIZE have no more effect. They are controlled by their counterparts in the dpdk {} stanza namely num-rx-queues and num-rx-desc
vpp_config_template: |-
    unix {
      nodaemon
      full-coredump
      cli-listen /var/run/vpp/cli.sock
    }
    api-trace { on }
    cpu {
        main-core 1
        workers 0
    }
    socksvr {
        socket-name /var/run/vpp/vpp-api.sock
    }
    dpdk {
      dev __PCI_DEVICE_ID__ { num-rx-queues 1  num-tx-queues 1 }
    }
    plugins {
        plugin default { enable }
        plugin calico_plugin.so { enable }
    }

Without hugepages

DPDK can also run without hugepages with the a configuration similar to the previous one

  • Pass CALICOVPP_NATIVE_DRIVER = none to the vpp container
  • The vpp config in the calico-config ConfigMap should look like the following, with __PCI_DEVICE_ID__ automatically populated with that of CALICOVPP_INTERFACE at startup
  • CALICOVPP_RX_QUEUES and CALICOVPP_RING_SIZE have no more effect. They are controlled by their counterparts in the dpdk {} stanza namely num-rx-queues and num-rx-desc

You also need to tell dpdk to no try allocating hugepages on its own

  • dpdk { no-hugetlb iova-mode va } does this for the dpdk plugin
  • buffers { no-hugetlb } does this for the buffers backing VPP’s packets

Caution: This won’t run with unsafe_iommu on. You need to echo N | sudo tee /sys/module/vfio/parameters/enable_unsafe_noiommu_mode

vpp_config_template: |-
    unix {
      nodaemon
      full-coredump
      cli-listen /var/run/vpp/cli.sock
    }
    api-trace { on }
    cpu {
        main-core 1
        workers 0
    }
    socksvr {
        socket-name /var/run/vpp/vpp-api.sock
    }
    dpdk {
      dev __PCI_DEVICE_ID__ { num-rx-queues 1  num-tx-queues 1 }
      iova-mode va
      no-hugetlb
    }
    buffers {
      no-hugetlb
    }
    plugins {
        plugin default { enable }
        plugin calico_plugin.so { enable }
    }

Using native drivers with vpp’s CLI

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

  • Pass CALICOVPP_NATIVE_DRIVER = none to the vpp container
  • Same as before, you should remove the dpdk { ... } section in vpp_config_template and update the plugins { ... } definitions as follows
  • Also add a exec /etc/vpp/startup.exec entry in unix { .. }
vpp_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 }
    }

Then update the CALICOVPP_CONFIG_EXEC_TEMPLATE environment variable to pass the interface creation cli(s).

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. Different drivers will have different requirements.