$config .= " vxlan-id $tag\n" if $tag;
$config .= " vxlan-svcnodeip $multicastaddress\n" if $multicastaddress;
$config .= " vxlan-physdev $iface\n" if $iface;
+ $config .= " mtu $mtu\n" if $mtu;
$config .= "\n";
$config .= "auto $vnetid\n";
$config .= "iface $vnetid inet manual\n";