// registerLinks writes the links to a file.
func (daemon *Daemon) registerLinks(container *container.Container, hostConfig *containertypes.HostConfig) error {
if hostConfig == nil || hostConfig.NetworkMode.IsUserDefined() {
return nil
}
for _, l := range hostConfig.Links {
name, alias, err := runconfigopts.ParseLink(l)
if err != nil {
return err
}
child, err := daemon.GetContainer(name)
if err != nil {
//An error from daemon.GetContainer() means this name could not be found
return fmt.Errorf("Could not get container for %s", name)
}
for child.HostConfig.NetworkMode.IsContainer() {
parts := strings.SplitN(string(child.HostConfig.NetworkMode), ":", 2)
child, err = daemon.GetContainer(parts[1])
if err != nil {
return fmt.Errorf("Could not get container for %s", parts[1])
}
}
if child.HostConfig.NetworkMode.IsHost() {
return runconfig.ErrConflictHostNetworkAndLinks
}
if err := daemon.registerLink(container, child, alias); err != nil {
return err
}
}
// After we load all the links into the daemon
// set them to nil on the hostconfig
return container.WriteHostConfig()
}
func (daemon *Daemon) allocateNetwork(container *container.Container) error {
controller := daemon.netController
// Cleanup any stale sandbox left over due to ungraceful daemon shutdown
if err := controller.SandboxDestroy(container.ID); err != nil {
logrus.Errorf("failed to cleanup up stale network sandbox for container %s", container.ID)
}
updateSettings := false
if len(container.NetworkSettings.Networks) == 0 {
if container.Config.NetworkDisabled || container.HostConfig.NetworkMode.IsContainer() {
return nil
}
err := daemon.updateContainerNetworkSettings(container, nil)
if err != nil {
return err
}
updateSettings = true
}
for n, nConf := range container.NetworkSettings.Networks {
if err := daemon.connectToNetwork(container, n, nConf, updateSettings); err != nil {
return err
}
}
return container.WriteHostConfig()
}
// migrateLegacySqliteLinks migrates sqlite links to use links from HostConfig
// when sqlite links were used, hostConfig.Links was set to nil
func (daemon *Daemon) migrateLegacySqliteLinks(db *graphdb.Database, container *container.Container) error {
// if links is populated (or an empty slice), then this isn't using sqlite links and can be skipped
if container.HostConfig == nil || container.HostConfig.Links != nil {
return nil
}
logrus.Debugf("migrating legacy sqlite link info for container: %s", container.ID)
fullName := container.Name
if fullName[0] != '/' {
fullName = "/" + fullName
}
// don't use a nil slice, this ensures that the check above will skip once the migration has completed
links := []string{}
children, err := db.Children(fullName, 0)
if err != nil {
if !strings.Contains(err.Error(), "Cannot find child for") {
return err
}
// else continue... it's ok if we didn't find any children, it'll just be nil and we can continue the migration
}
for _, child := range children {
c, err := daemon.GetContainer(child.Entity.ID())
if err != nil {
return err
}
links = append(links, c.Name+":"+child.Edge.Name)
}
container.HostConfig.Links = links
return container.WriteHostConfig()
}
func (daemon *Daemon) allocateNetwork(container *container.Container) error {
controller := daemon.netController
if daemon.netController == nil {
return nil
}
// Cleanup any stale sandbox left over due to ungraceful daemon shutdown
if err := controller.SandboxDestroy(container.ID); err != nil {
logrus.Errorf("failed to cleanup up stale network sandbox for container %s", container.ID)
}
updateSettings := false
if len(container.NetworkSettings.Networks) == 0 {
if container.Config.NetworkDisabled || container.HostConfig.NetworkMode.IsContainer() {
return nil
}
err := daemon.updateContainerNetworkSettings(container, nil)
if err != nil {
return err
}
updateSettings = true
}
// always connect default network first since only default
// network mode support link and we need do some setting
// on sandbox initialize for link, but the sandbox only be initialized
// on first network connecting.
defaultNetName := runconfig.DefaultDaemonNetworkMode().NetworkName()
if nConf, ok := container.NetworkSettings.Networks[defaultNetName]; ok {
cleanOperationalData(nConf)
if err := daemon.connectToNetwork(container, defaultNetName, nConf.EndpointSettings, updateSettings); err != nil {
return err
}
}
var (
networks []string
epConfigs []*network.EndpointSettings
)
for n, epConf := range container.NetworkSettings.Networks {
if n == defaultNetName {
continue
}
networks = append(networks, n)
epConfigs = append(epConfigs, epConf)
}
for i, epConf := range epConfigs {
cleanOperationalData(epConf)
if err := daemon.connectToNetwork(container, networks[i], epConf.EndpointSettings, updateSettings); err != nil {
return err
}
}
return container.WriteHostConfig()
}
func (daemon *Daemon) allocateNetwork(container *container.Container) error {
start := time.Now()
controller := daemon.netController
if daemon.netController == nil {
return nil
}
// Cleanup any stale sandbox left over due to ungraceful daemon shutdown
if err := controller.SandboxDestroy(container.ID); err != nil {
logrus.Errorf("failed to cleanup up stale network sandbox for container %s", container.ID)
}
updateSettings := false
if len(container.NetworkSettings.Networks) == 0 {
if container.Config.NetworkDisabled || container.HostConfig.NetworkMode.IsContainer() {
return nil
}
daemon.updateContainerNetworkSettings(container, nil)
updateSettings = true
}
// always connect default network first since only default
// network mode support link and we need do some setting
// on sandbox initialize for link, but the sandbox only be initialized
// on first network connecting.
defaultNetName := runconfig.DefaultDaemonNetworkMode().NetworkName()
if nConf, ok := container.NetworkSettings.Networks[defaultNetName]; ok {
cleanOperationalData(nConf)
if err := daemon.connectToNetwork(container, defaultNetName, nConf.EndpointSettings, updateSettings); err != nil {
return err
}
}
// the intermediate map is necessary because "connectToNetwork" modifies "container.NetworkSettings.Networks"
networks := make(map[string]*network.EndpointSettings)
for n, epConf := range container.NetworkSettings.Networks {
if n == defaultNetName {
continue
}
networks[n] = epConf
}
for netName, epConf := range networks {
cleanOperationalData(epConf)
if err := daemon.connectToNetwork(container, netName, epConf.EndpointSettings, updateSettings); err != nil {
return err
}
}
if err := container.WriteHostConfig(); err != nil {
return err
}
networkActions.WithValues("allocate").UpdateSince(start)
return nil
}
func (daemon *Daemon) allocateNetwork(container *container.Container) error {
controller := daemon.netController
// Cleanup any stale sandbox left over due to ungraceful daemon shutdown
if err := controller.SandboxDestroy(container.ID); err != nil {
logrus.Errorf("failed to cleanup up stale network sandbox for container %s", container.ID)
}
updateSettings := false
if len(container.NetworkSettings.Networks) == 0 {
mode := container.HostConfig.NetworkMode
if container.Config.NetworkDisabled || mode.IsContainer() {
return nil
}
networkName := mode.NetworkName()
if mode.IsDefault() {
networkName = controller.Config().Daemon.DefaultNetwork
}
if mode.IsUserDefined() {
n, err := daemon.FindNetwork(networkName)
if err != nil {
return err
}
networkName = n.Name()
}
container.NetworkSettings.Networks = make(map[string]*networktypes.EndpointSettings)
container.NetworkSettings.Networks[networkName] = new(networktypes.EndpointSettings)
updateSettings = true
}
for n := range container.NetworkSettings.Networks {
if err := daemon.connectToNetwork(container, n, updateSettings); err != nil {
return err
}
}
return container.WriteHostConfig()
}
//分配网络的主要代码。
func (daemon *Daemon) allocateNetwork(container *container.Container) error {
//controller是一个libnetwork.NetworkController的接口，主要有如下方法：
/*
type NetworkController interface {
// ID provides an unique identity for the controller
ID() string
// Config method returns the bootup configuration for the controller
Config() config.Config
// Create a new network. The options parameter carries network specific options.
NewNetwork(networkType, name string, options ...NetworkOption) (Network, error)
// Networks returns the list of Network(s) managed by this controller.
Networks() []Network
// WalkNetworks uses the provided function to walk the Network(s) managed by this controller.
WalkNetworks(walker NetworkWalker)
// NetworkByName returns the Network which has the passed name. If not found, the error ErrNoSuchNetwork is returned.
NetworkByName(name string) (Network, error)
// NetworkByID returns the Network which has the passed id. If not found, the error ErrNoSuchNetwork is returned.
NetworkByID(id string) (Network, error)
// NewSandbox cretes a new network sandbox for the passed container id
NewSandbox(containerID string, options ...SandboxOption) (Sandbox, error)
// Sandboxes returns the list of Sandbox(s) managed by this controller.
Sandboxes() []Sandbox
// WlakSandboxes uses the provided function to walk the Sandbox(s) managed by this controller.
WalkSandboxes(walker SandboxWalker)
// SandboxByID returns the Sandbox which has the passed id. If not found, a types.NotFoundError is returned.
SandboxByID(id string) (Sandbox, error)
// SandboxDestroy destroys a sandbox given a container ID
SandboxDestroy(id string) error
// Stop network controller
Stop()
// ReloadCondfiguration updates the controller configuration
ReloadConfiguration(cfgOptions ...config.Option) error
}
*/
controller := daemon.netController
if daemon.netController == nil {
return nil
}
// Cleanup any stale sandbox left over due to ungraceful daemon shutdown
//清除sandbox的相关信息，这个时候容器就没有IP地址了
if err := controller.SandboxDestroy(container.ID); err != nil {
logrus.Errorf("failed to cleanup up stale network sandbox for container %s", container.ID)
}
updateSettings := false
if len(container.NetworkSettings.Networks) == 0 {
if container.Config.NetworkDisabled || container.HostConfig.NetworkMode.IsContainer() {
return nil
}
err := daemon.updateContainerNetworkSettings(container, nil)
if err != nil {
return err
}
updateSettings = true
}
//容器可能添加了多个网络，因此需要对每一网络进行连接。
//其中,n代表网络的名字或者id，nConf代表网络的配置。
for n, nConf := range container.NetworkSettings.Networks {
if err := daemon.connectToNetwork(container, n, nConf, updateSettings); err != nil {
return err
}
}
//更新/var/lib/docker/containers/XXX/hosts文件，即容器的/etc/hosts文件。
return container.WriteHostConfig()
}