I explain how to set up Juniper emulation using Virtual Box and the JunOS12.ova file. This tutorial relates to CBT Nuggets' Juniper Networks Certified Associate Junos (JNCIA-Junos) JN0-102 training course: http://cbt.gg/1svXcZ5. Try CBT Nuggets free for 7 days: http://cbt.gg/1lAwo4L.