Setting up a temporary 2nd instance of pihole - port conflicts?

[DL6ER]

@Valiceemo

But, it dawned on me i may have conflicts with ports etc. as i will be, albeit briefly, running 2 instances at the same time.

I will comment on the "etc.":

@Valiceemo

So i was planning on using an old spare Pi have to setup pihole, unbound and wiregaurd, whilst keeping the OG pihole running, and then swapping out the sd card.

This sounds like you want to configure your replacement Pi-hole with the same IP address than the old one, right? So you don't have to go to the router settings and change the address.

This may very well result in a (serious) conflict as no address is allowed to exist twice. So, when changing the IP address of the replacement, make sure to disconnect the first one before the two-devices-using-one-address issue arises. I'd likely take your entire network down, otherwise.