I've done this stuff for some time now and let me give you some guidelines
1) NEVER give a laptop a fixed/static address. Instead, set the router to
use the DHCP Reservation on its hardware MAC address. WHY? Because when you
take the laptop on a trip or just down to the local coffee shop, it will never
connect properly - - you coerse it to work on one and only one router - - yours.
2) If at all possible (meaning you can control ALL devices), use just one subnet
{eg 192.168.1.1} and let the router with this address control ALL dhcp assignments.
This means, if you have multiple physical routers daisy changed A->B->C,
then only ONE can make DHCP assignments ==>A and B,C should have DHCP disabled.
3) if you *must* tollerate connections from different subnets
{ 192.168.1.1, 192.168.2.1, 192.168.3.1 }, then you *MUST* learn to create
Persistent Routes.
{btw: a switch does not have an IP address and makes not DHCP assignments}
For myself, I have TWO routers
Code:
modem==>routerA - - eop connection to a remote room
| |
| V
| WiFi Router --> Tv and Guest connections
|
+ -- wired systems {Mac, Linux, & Laptop}
4) I disabled DHCP in the wifi router, left the WAN slot on it
empty and connected LAN->LAN from eop device->WiFi router
5) known wired devices get MAC address reserved IP addresses <100
6) unknown devices (aka the WiFi) get addresses > 100
(5-6) allow the firewall to control which devices get access to shares.
The above creates a single subnet and all devices can use the default route 0.0.0.0 192.168.1.1
and allow sharing between all devices (assuming the firewalls on each so allow).
The other advantage of a single subnet, is you can add devices easily.