I just bought a new Asus RT-N12D1 router and a Asus GX-1051 V3 Gigabit switch and I'm having trouble connecting my desktop to the switch. I know the modem I have works, its a Motorola SB6121. The router works great cause I have it setup already and I know the switch works cause its connected to modem and the router is connected to the switch and my laptop and phone both connect to the router and get to the internet just fine, I can connect my desktop to the router to get to the internet but I want my desktop to go through the switch. I'm not sure what I'm doing wrong. I'm using brand new cat6 cables and brand new equipment.
Switches marketed for home users are always "unmanaged switch" and supports Auto-MDIX nowadays, there are no settings to tinker with both on the switch and router side.
From your post:
"...... the switch works cause its connected to modem and the router is connected to the switch and my laptop and phone both connect to the router and get to the internet just fine.."
I am assuming your config as:
In this setup, any devices plugged directly into an empty port in the switch will not get an ip from router DHCP and no traffic from router LAN side will be routed to the devices.
What you need to do:
FYI, all the LAN port from the router actually belongs to an internal switch.
I would do that but the ports on the router are fast Ethernet. If they were gigabit, I wouldn't have gotten the gigabit switch in the first place. The modem has a gigabit Ethernet, the router has fast Ethernet ports and the switch has gigabit ports. I know it works cause I did it before with an older eight port fast Ethernet switch but I want to use the gigabit switch for my computers.
You need to set up the modem as a simple pass-through so you will need to disable any routing capabilities it has on it.
Then connect the modem to the router via the routers WAN port.
You can then connect the switch to any one of the Ethernet ports on the router and any other devices to the switch.
This setup will give all the devices connected to the switch a Gbit connection between them but 100Mbit connection outward to the internet.
Buying a fast Ethernet router when you have Gbit connections on either side may have been a bad idea but this is the correct way to set up your network. No matter what you do all of the connected devices need to have access to the internet so they will have to get that access from the router, access through the router means fast Ethernet I'm afraid.
The only other option you have is to allow your modem to do all the routing and use the asus router as an access point.
In this scenario all the cabled devices will get Gbit Ethernet but the wireless clients will have to accept the fast Ethernet.
Here you will need to disable all of the routing capabilities from the Asus and only use the Wifi.