So i have 4 computers connected to a WiFi router since there is only 1 ethernet cable running to that room, and we are moving soon and i dont want to setup a punch block or anything. The WiFi router is ASUS RT-AC68R (AC1900). It was working before but now the computers cannot see each other. Let me elaborate.
We have our ISP, that cable runs to our firewall, then one single cable runs to a rack mount switch board, then from there 64 cables run to 63 different computers. All those computers can see each other, that is good. But the 64th slot is used to go to our Wifi Router, and there are 4 more computers connected there, those 4 computers can see each other, and the 63 computers can see each other, but those 2 groups can NOT see each other. This just started happening when i did a factory reset on the Wifi Router. When i log into the router, i get an error "The WAN IP is not the external IP. External IP-based services will not work." I think this is the issue, but i cannot find anything on the web to fix my issue. i have read the manual and i have not been able to find an answer. I have looked at the NAT settings, and have enabled NAT passthrough and turned ON "Respond to ICMP Echo (ping) Request from WAN. but nothing has worked. It used to work, so its just a setting on my wireless router, but i cannot see what. any help would be great.