: Cisco Traditional PAK license will be a challenge when you start to mange virtual devices. PAK license is tied to device’s SN (Serial Number). Take CSR1000v for example, SN will change when you create a new CSR which results old PAK license doesn’t work on new CSR. The recommended way is to manage virtual device license through Cisco Smart Licensing. In this video, I will walk through how to license CSR1000v with Smart Licensing.