08-19-2026 02:24 PM
You can export the configuration file and just perform a find and replace on 'ethernet1/1' to 'ethernet1/13' and then the same for the 'ethernet1/2' and 'ethernet1/14'. Import that configuration back into the firewall and then load and commit and you will swap over to the new interfaces assuming that Panorama isn't in play.
I would personally want to bring these two new interfaces online as a simple test (maybe with a new bogus zone configuration) just to ensure that it comes up properly prior to the cutover, but ultimately this is just to verify that they come online as expected.
I would personally not want to do this outside of a maintenance window since there will be momentary disruption as you migrate things and the risk of something not sending a GARP and updating immediately is possible. Without knowing more about your configuration this is likely the lowest risk way of making this change, but note that how you're connecting to your ISP could present issues in itself if their equipment will be seeing a new MAC and you have a basic business connection or something similar.
