Can I reach the device despite a different network and without a router?
I think I'm making a mistake and would like to ask again.
I've connected an old firewall to a switch for testing. The switch is connected to a client with an APIPA address of 169. The firewall has an IP of 192.168.1.1 (the default IP).
Why can I access the firewall interface despite using a different subnet? I'm still in training and testing a few things at home.
So either you have a DHCP server running somewhere or you use ipv6.