Appropriate use-case for M4100-D12G?

Not sure why you intend to go for a fully managed (and expensive) switch. Of course, it can be configured to do nice things like multiple VLANs, run a DHCP server for the additional VLAN based subnetworks, and last but not least some basic routing between the subnetworks.

[edit] Just realized for a 12 port GbE switch (with two shared copper/SFP ports) it isn't very expensive anymore.[/edit]

---

BK07 wrote:

I know that I can configure the M4100 to be a DHCP server, but what I'm not sure about is whether the M4100 can use DHCP to get its Internet-facing IP configuration like the Nighthawk does.  If it won't use DHCP to do that, can I manually configure those details to link my home to the Internet?

---

Nope, don't try this! The switch can't become a NAT router like the X6S. Keep the X6S as your NAT router for the Internet connection. Keep the DHCP server for the LAN on the X6S.

Aside, you seem to be confused about what is a DHCP server (this is to hand-out LAN subnet IP addresses) - the X6S router does have a DHCP client to get the public IP address on it's WAN/Internet interface.

Your set-up would look like this - regardless of the switch model:

Cable Modem <-> [WAN/Internet Port] X6S <-> [one LAN port] <-> Switch