Traffic flow while rebooting external E2E Controller

We are using an external E2E Controller for a small test deployment. We had to reboot the external E2E Controller VM today, as we started to get timeouts in cnMaestro when trying to make some topology changes, the reboot seem to sort the problem. However, this raised a question and some concern about whether the network, and existing nodes, will always continue to operate and pass customer traffic while the E2E Controller is unavailable for the couple of minutes it takes to reboot? Our testing indicates that this is the case, but I want to be sure that this is the expected behaviour.

Correct. Thats the expected behaviour.