Files
moby/libnetwork
Sebastiaan van Stijn 36151bd1d7 libnetwork/drivers/bridge: remove "ioctl" fallback code for legacy kernels
This code was forked from libcontainer (now runc) in
fb6dd9766e

From the description of this code:

> THIS CODE DOES NOT COMMUNICATE WITH KERNEL VIA RTNETLINK INTERFACE
> IT IS HERE FOR BACKWARDS COMPATIBILITY WITH OLDER LINUX KERNELS
> WHICH SHIP WITH OLDER NOT ENTIRELY FUNCTIONAL VERSION OF NETLINK

That comment was added as part of a refactor in;
4fe2c7a4db

Digging deeper into the code, it describes:

> This is more backward-compatible than netlink.NetworkSetMaster and
> works on RHEL 6.

That comment (and code) moved around a few times;

- moved into the libcontainer pkg: 6158ccad97
- moved within the networkdriver pkg: 4cdcea2047
- moved into the networkdriver pkg: 90494600d3

Ultimately leading to 7a94cdf8ed, which implemented
this:

> create the bridge device with ioctl
>
> On RHEL 6, creation of a bridge device with netlink fails.  Use the more
> backward-compatible ioctl instead.  This fixes networking on RHEL 6.

So from that information, it looks indeed to support RHEL 6, and Ubuntu 12.04
which are both EOL, and we haven't supported for a long time, so probably time
to remove this.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
2022-12-21 17:32:04 +01:00
..
2021-08-27 16:52:46 +02:00
2022-09-23 23:31:27 +02:00
2021-06-01 23:48:32 +00:00
2022-09-26 19:21:58 +02:00
2021-06-01 21:51:23 +00:00
2021-06-01 21:51:23 +00:00
2021-06-01 21:51:23 +00:00
2021-06-01 21:51:23 +00:00
2022-09-26 19:21:58 +02:00

libnetwork - networking for containers

Libnetwork provides a native Go implementation for connecting containers

The goal of libnetwork is to deliver a robust Container Network Model that provides a consistent programming interface and the required network abstractions for applications.

Design

Please refer to the design for more information.

Using libnetwork

There are many networking solutions available to suit a broad range of use-cases. libnetwork uses a driver / plugin model to support all of these solutions while abstracting the complexity of the driver implementations by exposing a simple and consistent Network Model to users.

package main

import (
	"fmt"
	"log"

	"github.com/docker/docker/pkg/reexec"
	"github.com/docker/docker/libnetwork"
	"github.com/docker/docker/libnetwork/config"
	"github.com/docker/docker/libnetwork/netlabel"
	"github.com/docker/docker/libnetwork/options"
)

func main() {
	if reexec.Init() {
		return
	}

	// Select and configure the network driver
	networkType := "bridge"

	// Create a new controller instance
	driverOptions := options.Generic{}
	genericOption := make(map[string]interface{})
	genericOption[netlabel.GenericData] = driverOptions
	controller, err := libnetwork.New(config.OptionDriverConfig(networkType, genericOption))
	if err != nil {
		log.Fatalf("libnetwork.New: %s", err)
	}

	// Create a network for containers to join.
	// NewNetwork accepts Variadic optional arguments that libnetwork and Drivers can use.
	network, err := controller.NewNetwork(networkType, "network1", "")
	if err != nil {
		log.Fatalf("controller.NewNetwork: %s", err)
	}

	// For each new container: allocate IP and interfaces. The returned network
	// settings will be used for container infos (inspect and such), as well as
	// iptables rules for port publishing. This info is contained or accessible
	// from the returned endpoint.
	ep, err := network.CreateEndpoint("Endpoint1")
	if err != nil {
		log.Fatalf("network.CreateEndpoint: %s", err)
	}

	// Create the sandbox for the container.
	// NewSandbox accepts Variadic optional arguments which libnetwork can use.
	sbx, err := controller.NewSandbox("container1",
		libnetwork.OptionHostname("test"),
		libnetwork.OptionDomainname("docker.io"))
	if err != nil {
		log.Fatalf("controller.NewSandbox: %s", err)
	}

	// A sandbox can join the endpoint via the join api.
	err = ep.Join(sbx)
	if err != nil {
		log.Fatalf("ep.Join: %s", err)
	}

	// libnetwork client can check the endpoint's operational data via the Info() API
	epInfo, err := ep.DriverInfo()
	if err != nil {
		log.Fatalf("ep.DriverInfo: %s", err)
	}

	macAddress, ok := epInfo[netlabel.MacAddress]
	if !ok {
		log.Fatalf("failed to get mac address from endpoint info")
	}

	fmt.Printf("Joined endpoint %s (%s) to sandbox %s (%s)\n", ep.Name(), macAddress, sbx.ContainerID(), sbx.Key())
}

Contributing

Want to hack on libnetwork? Docker's contributions guidelines apply.

Code and documentation copyright 2015 Docker, inc. Code released under the Apache 2.0 license. Docs released under Creative commons.