I am trying to use a Netgear gigabit switch (GS105) with a Motorola cable modem (MB8611). The Internet Service Provider is Xfinity. I’ve used this switch successfully with a different modem and ISP. With the Motorola modem-Xfinity combination, the switch is not working correctly. I can only get one device online at a time. When I plug in a second device, it says it can’t connect to the DHCP server and can’t get an IP address. Many thanks in advance for suggestions in simple, non-technical language :-)
Cable modem will only provide 1 public IP since that is all that Xfinity will provision. You need to connect a router with its WAN port to the modem and then all other devices to the router’s LAN ports.