package daemon import ( "fmt" "net/http" "runtime" "strings" "syscall" "time" "google.golang.org/grpc" "github.com/Sirupsen/logrus" apierrors "github.com/docker/docker/api/errors" "github.com/docker/docker/api/types" containertypes "github.com/docker/docker/api/types/container" "github.com/docker/docker/container" ) // ContainerStart starts a container. func (daemon *Daemon) ContainerStart(name string, hostConfig *containertypes.HostConfig, checkpoint string, checkpointDir string) error { if checkpoint != "" && !daemon.HasExperimental() { return apierrors.NewBadRequestError(fmt.Errorf("checkpoint is only supported in experimental mode")) } container, err := daemon.GetContainer(name) if err != nil { return err } if container.IsPaused() { return fmt.Errorf("Cannot start a paused container, try unpause instead.") } if container.IsRunning() { err := fmt.Errorf("Container already started") return apierrors.NewErrorWithStatusCode(err, http.StatusNotModified) } // Windows does not have the backwards compatibility issue here. if runtime.GOOS != "windows" { // This is kept for backward compatibility - hostconfig should be passed when // creating a container, not during start. if hostConfig != nil { logrus.Warn("DEPRECATED: Setting host configuration options when the container starts is deprecated and has been removed in Docker 1.12") oldNetworkMode := container.HostConfig.NetworkMode if err := daemon.setSecurityOptions(container, hostConfig); err != nil { return err } if err := daemon.mergeAndVerifyLogConfig(&hostConfig.LogConfig); err != nil { return err } if err := daemon.setHostConfig(container, hostConfig); err != nil { return err } newNetworkMode := container.HostConfig.NetworkMode if string(oldNetworkMode) != string(newNetworkMode) { // if user has change the network mode on starting, clean up the // old networks. It is a deprecated feature and has been removed in Docker 1.12 container.NetworkSettings.Networks = nil if err := container.CheckpointTo(daemon.containersReplica); err != nil { return err } } container.InitDNSHostConfig() } } else { if hostConfig != nil { return fmt.Errorf("Supplying a hostconfig on start is not supported. It should be supplied on create") } } // check if hostConfig is in line with the current system settings. // It may happen cgroups are umounted or the like. if _, err = daemon.verifyContainerSettings(container.HostConfig, nil, false); err != nil { return err } // Adapt for old containers in case we have updates in this function and // old containers never have chance to call the new function in create stage. if hostConfig != nil { if err := daemon.adaptContainerSettings(container.HostConfig, false); err != nil { return err } } return daemon.containerStart(container, checkpoint, checkpointDir, true) } // containerStart prepares the container to run by setting up everything the // container needs, such as storage and networking, as well as links // between containers. The container is left waiting for a signal to // begin running. func (daemon *Daemon) containerStart(container *container.Container, checkpoint string, checkpointDir string, resetRestartManager bool) (err error) { start := time.Now() container.Lock() defer container.Unlock() if resetRestartManager && container.Running { // skip this check if already in restarting step and resetRestartManager==false return nil } if container.RemovalInProgress || container.Dead { return fmt.Errorf("Container is marked for removal and cannot be started.") } // if we encounter an error during start we need to ensure that any other // setup has been cleaned up properly defer func() { if err != nil { container.SetError(err) // if no one else has set it, make sure we don't leave it at zero if container.ExitCode() == 0 { container.SetExitCode(128) } if err := container.CheckpointTo(daemon.containersReplica); err != nil { logrus.Errorf("%s: failed saving state on start failure: %v", container.ID, err) } container.Reset(false) daemon.Cleanup(container) // if containers AutoRemove flag is set, remove it after clean up if container.HostConfig.AutoRemove { container.Unlock() if err := daemon.ContainerRm(container.ID, &types.ContainerRmConfig{ForceRemove: true, RemoveVolume: true}); err != nil { logrus.Errorf("can't remove container %s: %v", container.ID, err) } container.Lock() } } }() if err := daemon.conditionalMountOnStart(container); err != nil { return err } if err := daemon.initializeNetworking(container); err != nil { return err } spec, err := daemon.createSpec(container) if err != nil { return err } createOptions, err := daemon.getLibcontainerdCreateOptions(container) if err != nil { return err } if resetRestartManager { container.ResetRestartManager(true) } if checkpointDir == "" { checkpointDir = container.CheckpointDir() } if daemon.saveApparmorConfig(container); err != nil { return err } if err := daemon.containerd.Create(container.ID, checkpoint, checkpointDir, *spec, container.InitializeStdio, createOptions...); err != nil { errDesc := grpc.ErrorDesc(err) contains := func(s1, s2 string) bool { return strings.Contains(strings.ToLower(s1), s2) } logrus.Errorf("Create container failed with error: %s", errDesc) // if we receive an internal error from the initial start of a container then lets // return it instead of entering the restart loop // set to 127 for container cmd not found/does not exist) if contains(errDesc, container.Path) && (contains(errDesc, "executable file not found") || contains(errDesc, "no such file or directory") || contains(errDesc, "system cannot find the file specified")) { container.SetExitCode(127) } // set to 126 for container cmd can't be invoked errors if contains(errDesc, syscall.EACCES.Error()) { container.SetExitCode(126) } // attempted to mount a file onto a directory, or a directory onto a file, maybe from user specified bind mounts if contains(errDesc, syscall.ENOTDIR.Error()) { errDesc += ": Are you trying to mount a directory onto a file (or vice-versa)? Check if the specified host path exists and is the expected type" container.SetExitCode(127) } return fmt.Errorf("%s", errDesc) } containerActions.WithValues("start").UpdateSince(start) return nil } // Cleanup releases any network resources allocated to the container along with any rules // around how containers are linked together. It also unmounts the container's root filesystem. func (daemon *Daemon) Cleanup(container *container.Container) { daemon.releaseNetwork(container) container.UnmountIpcMounts(detachMounted) if err := daemon.conditionalUnmountOnCleanup(container); err != nil { // FIXME: remove once reference counting for graphdrivers has been refactored // Ensure that all the mounts are gone if mountid, err := daemon.stores[container.Platform].layerStore.GetMountID(container.ID); err == nil { daemon.cleanupMountsByID(mountid) } } if err := container.UnmountSecrets(); err != nil { logrus.Warnf("%s cleanup: failed to unmount secrets: %s", container.ID, err) } for _, eConfig := range container.ExecCommands.Commands() { daemon.unregisterExecCommand(container, eConfig) } if container.BaseFS != "" { if err := container.UnmountVolumes(daemon.LogVolumeEvent); err != nil { logrus.Warnf("%s cleanup: Failed to umount volumes: %v", container.ID, err) } } container.CancelAttachContext() }