Connecting three routers to one modem

Jose Maria Rico

Honorable
Oct 3, 2013
3
0
10,510
Hello!

I currently have three routers and a modem. They are set up in cascade, like the instructions indicate in The Ultimate Modem/Router Setup Thread. The setup goes like this:

modem LAN -> main router WAN
main router LAN -> slave router 1 LAN
slave router 1 LAN -> slave router 2 LAN

DHCP is enabled only in the main router. This setup has worked perfectly so far; there are no conflicting IPs and the router transition as one moves around the house is clean and neat.

However, due to some changes in my house's internal cabling, I want to be able to connect each router directly to the modem (it has 4 ethernet LAN ports), and I want the network to behave as it is right now: just one single network with a single DHCP that assigns IP addresses. I'm not really sure how to go about this, because, for example, doing [modem LAN -> router WAN] for each router would result in separate internal networks.
 
Solution
Yes, that will work exactly.

The device you have:
"The Discus™ DRG A115 is an ADSL2+ router, with one RJ-11 WAN port, four 10/100Mbps Fast Ethernet ports and a single USB 1.1 port. "

So yes, it is a ADSL modem + router. It can perform all the DHCP functions necessary.

So you can turn all your existing routers into slaves, and hang them off the Discus thing.
Or...you could sell those routers, and get 2 or 3 actual switches. Which will work exactly the same, but with less configuration issues. Just plug them in.

USAFRet

Titan
Moderator
OK....

The modem, which seems to have 4 ports, would seem to be a modem+router, not just a modem.

If so, then THAT is what needs to be doing the DHCP assignment. The other routers would have DHCP turned off, and act as simple switches.

What is the specific make/model of this modem thing?
 

Jose Maria Rico

Honorable
Oct 3, 2013
3
0
10,510


Oh okay, I see... So maybe it would work if I did the same setup as I had before, but use the modem/router as the main router and then turn all the other into slaves?

The model is Pirelli Discus DRG A115.
 

USAFRet

Titan
Moderator
Yes, that will work exactly.

The device you have:
"The Discus™ DRG A115 is an ADSL2+ router, with one RJ-11 WAN port, four 10/100Mbps Fast Ethernet ports and a single USB 1.1 port. "

So yes, it is a ADSL modem + router. It can perform all the DHCP functions necessary.

So you can turn all your existing routers into slaves, and hang them off the Discus thing.
Or...you could sell those routers, and get 2 or 3 actual switches. Which will work exactly the same, but with less configuration issues. Just plug them in.
 
Solution