Techniques for implementing a provisional mode in a multi-mode network device (i.e., a network device that supports at least first and second modes of operation) are provided. According to one embodiment, the network device can receive, while running in the first mode, a request to enter the second mode. In response to the request, the network device can enter a third mode that is a provisional version of the second mode. Then, while running in the third mode, the network device can accept one or more configuration commands or settings for the second mode while simultaneously processing live network traffic according to the first mode.