Create great junos labs with Logical System and Tunnels. Works in vMX too!

Here’s a great article from 2012 on Junos logical systems and logical tunnel interfaces. MX routers support 15 logical systems per router and when you combine this with logical tunnel interfaces, you can make extremely complex lab networks with one or more MX routers. Here’s the article below along with some additional information about logical tunnel interfaces.

JUNOS Logical-System: A Great Way To Learn Junos & Prepare For Certification

Configuring Logical Tunnel Interfaces

Also, you don’t have an MX router laying around? No problem! This is fully supported on Juniper’s vMX.

Below is an example to enable tunnel services within a vMX router.

chassis {

    fpc 0 {

        pic 0 {

            tunnel-services {

                bandwidth 10g;


            interface-type ge;          

            number-of-ports 8;




    network-services enhanced-ip;


Here’s an example topology I created with logical systems and logical tunnel interfaces between the logical systems. In this example, there are two vMX routers with five logical systems each. This is like having ten routers total. Within the MXs, the logical systems are interconnected via logical tunnel interfaces which saves the ge interfaces for just interconnecting the vMXs together. That’s important due to the current limitation of 8 useable revenue interfaces on vMX routers.


Have fun making great labs with this!