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CNI v1.0 documentation is no longer actively maintained. The version you are currently viewing is a static snapshot. For up-to-date documentation, see the latest release, v1.1, or the current documentation.

bandwidth plugin



This plugin provides a way to use and configure Linux’s Traffic control (tc) subsystem. tc encompasses the sets of mechanisms and operations by which packets are queued for transmission/reception on a network interface.

This plugin configures a token bucket filter (tbf) queuing discipline (qdisc) on both ingress and egress traffic. Resulting in traffic being shaped when reading / writing.

Due to limitations on tc shaping rules for ingress, this plugin creates an Intermediate Functional Block device (ifb) to redirect packets from the host interface. tc tbf is then applied to the ifb device. The packets that were redirected to the ifb devices, are written OUT (and shaped) to the host interface.

This plugin is only useful when used in addition to other plugins.


The bandwidth plugin applies traffic shaping to interfaces (as described above) created by previously applied plugins.

The following is an example json configuration list for creating a ptp between the host -> container via veth interfaces, whereby traffic is shaped by the bandwidth plugin:

  "cniVersion": "0.3.1",
  "name": "mynet",
  "plugins": [
      "type": "ptp",
      "ipMasq": true,
      "mtu": 512,
      "ipam": {
          "type": "host-local",
          "subnet": ""
      "dns": {
        "nameservers": [ "" ]
      "name": "slowdown",
      "type": "bandwidth",
      "ingressRate": 123,
      "ingressBurst": 456,
      "egressRate": 123,
      "egressBurst": 456

The result is an ifb device in the host namespace redirecting to the host-interface, with tc tbf applied on the ifb device and the container-interface

Network configuration reference

Both ingressRate and ingressBurst must be set in order to limit ingress bandwidth. If neither one is set, then ingress bandwidth is not limited. Both egressRate and egressBurst must be set in order to limit egress bandwidth. If neither one is set, then egress bandwidth is not limited.

tc tbf documentation