pfSense: Two subnets on same interface?

I replaced my old router with a pfSense box. At the same time, I also changed my old IP scheme subnet scheme so I’m using a completely different subnet. Unfortunately, I had some devices that weren’t set to use DHCP and have hard-coded addresses in their settings. Now I can’t get to them without pulling them out of the corner and hooking up a monitor/keyboard. I’d like to find a way to map my old subnet onto the interface so I can still get to those devices and fix them. (I guess another way would be to statically set my PC to that old subnet temporarily). But I’d like to find a way to do it in pfSense if I can. I suspect it is with IP aliases and although the documentation explains EXACTLY how those work, it doesn’t tell how to implement them in real life. I think I also need to set 1:1 NAT or other firewall rules…

Interface: LAN
Old subnet:
New subnet:

So all my devices with DHCP now have 172.17.x.x addresses, but I’d still like to be able to get to my 192.168.60.x devices that are connected on the same physical interface (switche(s) connected to that itnerface).

Thanks for any tips!

I’d like the experts to chime in here, but you can’t really have two subnets on one interface unless you’ve implemented something like VLANs.

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In a high availability setup you can have more than one IP address on an interface, but the caveat is that they need to be on the same subnet. Perhaps there is a way but I doubt it will be straight forward.

It will be easier to get a another router and access your devices that way.

That is the second most common way to fix it, the first is changing the devices prior to changing the subnet.

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