If the DHCP function of your router is enabled (check your router configuration), it will automatically assign IP's to you LAN Devices (may lead to IP conflicts). Switch to static IP's and configure your Antminers and your other LAN Devices (Laptops, Tablets, Smartphones ect.) properly. Just make sure, they are within the same IP Range and no two devices share the same IP. By default, the Antminers use the same IP, so you can only access one of them. Change the static IP and you should be able to access another Antminer and so on.
Example Configuration (all IP's within the same range 192.168.1.0 to 192.168.1.255)
Router DCHP function: deactivated (-> static IP's)
IP of your router (gateway): 192.168.1.2
Network Mask (for all your devices): 255.255.255.0
Antminer #1 Default IP: 192.168.1.99 -> change to: 192.168.1.110
Antminer #2 Default IP: 192.168.1.99 -> change to: 192.168.1.111
Antminer #3 Default IP: 192.168.1.99 -> change to: 192.168.1.112
Antminer #4 Default IP: 192.168.1.99 -> change to: 192.168.1.113
Antminer #5 Default IP: 192.168.1.99 -> change to: 192.168.1.114
Laptop IP: 192.168.1.160
Smartphone IP: 192.168.1.161
SmartTV IP: 192.168.1.162
The DNS 8.8.8.8 should be fine. It's from google, but any other DNS will do it too.
Thanks! I will give this a try as soon as I get home from work.