And then grep a bit to know what the prime interface is and you just configure that in the first time wizard or through the isomorphic tool.
Given that most firewalls don't change interfaces that much you can update you recovery USB stick everytime you make a change.
It would mean you might automate it and just send a cab driver with a USB stick and a unit to remote location and get it up and running in no time in case of a hardware failure.
Or you might use SRAFAP. (Google won't help you here 😉 ((Students Running As Fast As Possible.))
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