My machine is connected to a switch (using an ethernet cable). In addition to the modem (with built-in router) this switch is also connected to several other routers. Using a standard netctl profile (Interface=eth0, Connection=ethernet, IP=dhcp), I'm  usually connected to the modem/router (192.168.100.1). However, today something went wrong  I got connected to one of the other routers (192.168.0.1).I'm now wondering about the proper way to set-up a netctl profile to always connect to the 192.168.100.1 modem/router. One option might be to set IP=static and use something like Address=('192.168.100.42/24'),Gateway='192.168.100.1'. However, when I tried something random like Address=('123.123.123.42/24'), Gateway='123.123.123.1' netctl did not complain. The output of ip addr also displayed 123.123.123.42/24, even though there is no 123.123.123.1 router connected to the switch.Basically my question is how to force netctl to connect to a certain router, using either IP=dhcp or IP=static.
Multiple routers connected to switch  how to connect to the right one using netctl
netctl