1. docker
  2. Commit 2aa673aed7cd10497d578a14a9550c75789e0a43
Browse code

Lazy initialize Volume on container Mount object

Currently on daemon start volumes are "created" which involves invoking
a volume driver if needed. If this process fails the mount is left in a
bad state in which there is no source or Volume set. This now becomes
an unrecoverable state in which that container can not be started. The
only way to fix is to restart the daemon and hopefully you don't get
another error on startup.

This change moves "createVolume" to be done at container start. If the
start fails it leaves it in the state in which you can try another
start. If the second start can contact the volume driver everything
will recover fine.

Signed-off-by: Darren Shepherd <darren@rancher.com>

Darren Shepherd authored on 2015/12/10 04:39:31
Showing 4 changed files
daemon/daemon.go
History View file @ 2aa673a
... ... 
@@ -283,10 +283,6 @@ func (daemon *Daemon) Register(container *container.Container) error {
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 		}
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 	}
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-	if err := daemon.prepareMountPoints(container); err != nil {
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-		return err
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-	}
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-
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 	return nil
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 }
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daemon/mounts.go
History View file @ 2aa673a
... ... 
@@ -8,20 +8,6 @@ import (
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 	volumestore "github.com/docker/docker/volume/store"
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 )
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-func (daemon *Daemon) prepareMountPoints(container *container.Container) error {
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-	for _, config := range container.MountPoints {
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-		if len(config.Driver) > 0 {
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-			v, err := daemon.volumes.GetWithRef(config.Name, config.Driver, container.ID)
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-			if err != nil {
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-				return err
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-			}
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-
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-			config.Volume = v
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-		}
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-	}
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-	return nil
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-}
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-
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 func (daemon *Daemon) removeMountPoints(container *container.Container, rm bool) error {
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 	var rmErrors []string
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 	for _, m := range container.MountPoints {
daemon/volumes_unix.go
History View file @ 2aa673a
... ... 
@@ -20,6 +20,14 @@ import (
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 func (daemon *Daemon) setupMounts(container *container.Container) ([]execdriver.Mount, error) {
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 	var mounts []execdriver.Mount
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 	for _, m := range container.MountPoints {
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+		// Lazy initialize m.Volume if needed.  This happens after a daemon restart
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+		if len(m.Driver) > 0 && m.Volume == nil {
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+			v, err := daemon.createVolume(m.Name, m.Driver, nil)
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+			if err != nil {
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+				return nil, err
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+			}
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+			m.Volume = v
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+		}
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 		path, err := m.Setup()
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 		if err != nil {
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 			return nil, err
daemon/volumes_windows.go
History View file @ 2aa673a
... ... 
@@ -18,6 +18,14 @@ import (
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 func (daemon *Daemon) setupMounts(container *container.Container) ([]execdriver.Mount, error) {
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 	var mnts []execdriver.Mount
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 	for _, mount := range container.MountPoints { // type is volume.MountPoint
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+		// Lazy initialize m.Volume if needed.  This happens after a daemon restart
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+		if len(m.Driver) > 0 && m.Volume == nil {
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+			v, err := daemon.createVolume(m.Name, m.Driver, nil)
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+			if err != nil {
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+				return nil, err
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+			}
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+			m.Volume = v
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+		}
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 		// If there is no source, take it from the volume path
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 		s := mount.Source
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 		if s == "" && mount.Volume != nil {