Question Config Q: Modem<-->Router1<-->Router2<-->LAN

[tomyak]

Hi.

For my own bizarre needs I want to know how to put a second router between a cable modem (WAN) and a small LAN. I know that most sensible people have a single router between these things in a very small LAN environment. What do I need to do to configure (assume wired only) the two routers to have connectivity between WAN and LAN? I can worry about DHCP/fixed IP addressing & wireless questions on my own.

If it matters, assume that all local wired/wireless LAN devices are connected to LAN-side router (which will likely also provide DHCP service to them). Guest wireless (used for internet access only) will likely be set-up on the WAN-side router.

Useful guidance much appreciated. (Again, just to the question of connectivity between the LAN, through to the two chained routers and out to the modem).

 

[bill001g]

In the simplest cases you just need to hook it up and make sure you use different subnets for the lan off the first router and the lan off the second router. If they are the same the second router will generally complain and not function because its wan and lan are on the same subnet.

Security wise the device off the second router can access the devices off the first router but not the reverse. So if I read it correctly you guest users will not be able to access the machines on lan behind the second router.

There are issues doing this if you need port forwarding or UPnP to function. This is mostly a gaming issue and mostly with consoles

 

[tomyak]

In the simplest cases you just need to hook it up and make sure you use different subnets for the lan off the first router and the lan off the second router. If they are the same the second router will generally complain and not function because its wan and lan are on the same subnet.

Security wise the device off the second router can access the devices off the first router but not the reverse. So if I read it correctly you guest users will not be able to access the machines on lan behind the second router.

There are issues doing this if you need port forwarding or UPnP to function. This is mostly a gaming issue and mostly with consoles

Thanks.

Very practically, do I connect the LAN-side router WAN port to any of the LAN-side ports on the WAN-side router?

 

[bill001g]

Hook the lan port of the main router to the wan port of the second router.

 

[tomyak]

Hook the lan port of the main router to the wan port of the second router.

Finally got things hooked up yesterday and it's working fine. Thanks for your assistance.

 

[failboat]

True guest separation is done with vlans and layer2 client isolation. this makes it's only available path WAN. unifi equipment is easy to configure this.