@@ -18,6 +18,7 @@ type DaemonConfig struct {

 	DefaultIp                   net.IP

 	InterContainerCommunication bool

 	GraphDriver                 string

+	Mtu                         int

 }

 // ConfigFromJob creates and returns a new DaemonConfig object

@@ -41,5 +42,10 @@ func ConfigFromJob(job *engine.Job) *DaemonConfig {

 	config.DefaultIp = net.ParseIP(job.Getenv("DefaultIp"))

 	config.InterContainerCommunication = job.GetenvBool("InterContainerCommunication")

 	config.GraphDriver = job.Getenv("GraphDriver")

+	if mtu := job.GetenvInt("Mtu"); mtu != -1 {

+		config.Mtu = mtu

+	} else {

+		config.Mtu = DefaultNetworkMtu

+	}

 	return &config

 }

@@ -582,7 +582,7 @@ func (container *Container) Start() (err error) {

 		params = append(params,

 			"-g", network.Gateway,

 			"-i", fmt.Sprintf("%s/%d", network.IPAddress, network.IPPrefixLen),

-			"-mtu", "1500",

+			"-mtu", strconv.Itoa(container.runtime.config.Mtu),

 		)

 	}

@@ -40,6 +40,7 @@ func main() {

 		flInterContainerComm = flag.Bool("icc", true, "Enable inter-container communication")

 		flGraphDriver        = flag.String("s", "", "Force the docker runtime to use a specific storage driver")

 		flHosts              = docker.NewListOpts(docker.ValidateHost)

+		flMtu                = flag.Int("mtu", docker.DefaultNetworkMtu, "Set the containers network mtu")

 	)

 	flag.Var(&flDns, "dns", "Force docker to use specific DNS servers")

 	flag.Var(&flHosts, "H", "Multiple tcp://host:port or unix://path/to/socket to bind in daemon mode, single connection otherwise")

@@ -87,6 +88,7 @@ func main() {

 		job.Setenv("DefaultIp", *flDefaultIp)

 		job.SetenvBool("InterContainerCommunication", *flInterContainerComm)

 		job.Setenv("GraphDriver", *flGraphDriver)

+		job.SetenvInt("Mtu", *flMtu)

 		if err := job.Run(); err != nil {

 			log.Fatal(err)

 		}

@@ -37,6 +37,7 @@ To list available commands, either run ``docker`` with no parameters or execute

       -icc=true: Enable inter-container communication

       -ip="0.0.0.0": Default IP address to use when binding container ports

       -iptables=true: Disable docker's addition of iptables rules

+      -mtu=1500: Set the containers network mtu

       -p="/var/run/docker.pid": Path to use for daemon PID file

       -r=true: Restart previously running containers

       -s="": Force the docker runtime to use a specific storage driver

@@ -32,6 +32,7 @@ func mkRuntime(f utils.Fataler) *docker.Runtime {

 	config := &docker.DaemonConfig{

 		Root:        root,

 		AutoRestart: false,

+		Mtu:         docker.DefaultNetworkMtu,

 	}

 	r, err := docker.NewRuntimeFromDirectory(config)

 	if err != nil {

@@ -19,6 +19,7 @@ import (

 const (

 	DefaultNetworkBridge = "docker0"

 	DisableNetworkBridge = "none"

+	DefaultNetworkMtu    = 1500

 	portRangeStart       = 49153

 	portRangeEnd         = 65535

 	siocBRADDBR          = 0x89a0

@@ -118,7 +119,6 @@ func CreateBridgeIface(config *DaemonConfig) error {

 		"192.168.44.1/24",

 	}

-

 	nameservers := []string{}

 	resolvConf, _ := utils.GetResolvConf()

 	// we don't check for an error here, because we don't really care