HI. I am trying to send from pi master to a Wled device 192.168.100.5 . This connects wirelessly to a modem which is 192.168.100.1. I have connected it to Eth 1 on the pi. Question I have is this. Should the static address on that Eth be set to 192.168.100.1 ? Had it working last year, can't seem to make it work at the moment.
no it should NOT be 192.168.100.1, that is the router's IP address. Every network devices needs a unique IP address.