Merge pull request #16 from PouuleT/mtu

Add option to specify MTU

Author: PouuleT

README.md

@@ -26,6 +26,8 @@
           loss added on the interface in percentage (default 0)
     -jitter uint
           jitter added on the interface in ms (default 0)
+    -mtu int
+          MTU of the interface
     -latency uint
           latency added on the interface in ms (default 0)
 ```

main.go

@@ -16,6 +16,7 @@ import (
 
 var ip, command, gateway, intf, logLevel, nsPath, mac string
 var latency, jitter uint
+var mtu int
 var loss float64
 var log = logrus.New()
 var namespace, origns *netns.NsHandle
@@ -37,6 +38,7 @@ func init() {
 	flag.UintVar(&latency, "latency", 0, "latency added on the interface in ms")
 	flag.UintVar(&jitter, "jitter", 0, "jitter added on the interface in ms")
 	flag.Float64Var(&loss, "loss", 0, "loss added on the interface in percentage")
+	flag.IntVar(&mtu, "mtu", 0, "MTU of the interface")
 	flag.StringVar(
 		&nsPath,
 		"ns-path",
@@ -148,6 +150,14 @@ func main() {
 		return
 	}
 
+	// ============================= Set the mtu of the macVlan interface
+
+	err = setMacVlanMTU(link)
+	if err != nil {
+		log.Warn("Error while setting vlan MTU: ", err)
+		return
+	}
+
 	// ============================== Create the new Namespace
 
 	namespace, err = newNS()

net.go

@@ -105,3 +105,17 @@ func setMacVlanMacAddr(link *netlink.Link) error {
 	}
 	return nil
 }
+
+func setMacVlanMTU(link *netlink.Link) error {
+	// If a mtu was specified, set it now
+	if mtu == 0 {
+		return nil
+	}
+	log.Debugf("Setting macVlan with specified MTU : %s", mtu)
+	err = netlink.LinkSetMTU(*link, mtu)
+	if err != nil {
+		log.Warn("Error while setting given mtu on macVlan: ", err)
+		return err
+	}
+	return nil
+}