Sharing resources across two subnets?

[MacMarcus]

Hi All!

I have a DSL modem router (router 1) connected to a DSL line, with 192.168.x.x IP class and 255.255.255.0 subnet mask.
The router offers wifi connectivity as well.
On one of the Ethernet ports, I have connected a wifi router (router 2) with a static IP 192.168.1.100 on WAN port, which distributes 172.16.0.x IP addresses, with a 255.255.0.0 subnet mask. A NAS (static IP, Time Machine capable), an Apple TV and a Blu-Ray player are connected to this router, which offers wifi connectivity as well.

Internet connection works like a charm from both routers, with cable or via wifi.

Now, if I connect to router 2 I can obviously discover the SMB resources and use them. If I connect to 192.168.1.254 (router 1 IP address) from there, I can access router 1 and perform admin tasks from a different subnet.

If I connect to router 1, I can't see any of the resources under router 2 (fair enough, I expected this as they belong to separate subnets), but if I navigate to 192.168.1.100 (router 2 IP address), the NAS web front end will popup (NAS address in 172.16.0.199).

Now, how can I configure two routers to recognize and access the resources under router 2 when I am connected to router 1? Is there something I can do with my hardware? Is it suitable or I need different networking components/devices to accomplish this task?

Thanks in advance to anybody who will help.

Marco.

P.S.: choice of IP address on router 2 was chosen to avoid subnet conflicts, otherwise it would not have worked (as it happened with default settings, both routers were on 182.168.x.x and 255.255.255.0)

 

[jsmithepa]

Now you are aware this situation can be avoided by configuring the 2nd router as an access point and keep everybody on the same subnet.

 

[bill001g]

Pretty much you can't do this in a home network. The devices you call routers are really stupid they pretty much can only have 1 lan subnet and translate all the traffic to a single wan address. They are best called gateways because they are so restricted in function.

If you had actual routers this will pretty much just work in simple configurations. The routers are not manipulating the addresses with nat unless you tell them to and they know which subnet is on which interface.

Now if you only have a single machine on the second router you may be able to use DMZ options to make it work but your main issue is the NAT the second router is doing and there is no simple solution to this.

 

[MacMarcus]

Hi jsmithepa, thanks for your answer.
You are right, unfortunately I cannot install my devices under router 1, as this is placed in a laundry room and this is not the most convenient environment for such appliances! Therefore I am forced - from a network topological point of view - to use this cascading solution.
I omitted this info in my original post.

Cheers,
m.

 

[bill001g]

Running the router as a AP is more of a physical thing rather than a subnet thing. You would still place the equipment in the same locations. Some routers it is as simple as clicking to run the device as a AP other you have to do some minor recabling and configuration to make any router run as a AP>

 

[MacMarcus]

Hi bill001g,

Thanks for the answer, I agree on everything you wrote: so-called home routers are poorly configurable, and traffic routing is quite simple. My ISP router does not give the possibility to show up any routing table! Rules to be configured are few and very basic.
I am getting more convinced that I should go for more complex networking hardware. I have to understand if it's worth the expense as I would need just to ensure multimedia streaming from both network subnets.

Thanks again,

m.

 

[bill001g]

Unless you need a different subnet for some particular reason it is silly to even do in home network.

Used to be you used subnets to reduce the number of machines on one broadcast domain. Now equipment is so fast you can put over 1000 machines on 1 larger subnet and it has no negative impact.

You generally use a different subnet to break up say parts of a building. We use different subnet even when it would work with larger ones sometimes to help our 911 location software know what floor of a building to transmit to the emergency services when people use a IP phone that can be easily moved.

The only reason I have see in a home network to use multiple subnets is when you have some equipment that is being a pain. Some equipment has stupid restriction on what ip ranges it can use...or if you say surveillance cameras that actually stream data via broadcast that you would want separate.

 

[MacMarcus]

I understand your point, but I was forced to do so.
Basically if I have on router 1 a LAN IP pool of 192.168.0.x with a 255.255.255.0 subnet mask, router 2 WON'T let me assign a 192.168.1.x with same subnet. That was the reason. Routers are connected with fixed IP from LAN port on router 1 to WAN port on router 2. Is there any mistake in this? Is anything I am missing here?

 

[bill001g]

You cable to the lan port. Disable the DHCP on the second router. Set the ip to some address outside the DHCP pool of the first like 192.168.0.250

 

[MacMarcus]

You cable to the lan port. Disable the DHCP on the second router. Set the ip to some address outside the DHCP pool of the first like 192.168.0.250

 

[MacMarcus]

Okay, I'll give it a try.
To be on the safe side, so I have to connect from LAN to WAN ports and assign the WAN port address outside the first router pool, while deactivating the DHCP on second router. This way the first router should act as DHCP for any clients on whatever router they're connected?

 

[jsmithepa]

unfortunately I cannot install my devices under router 1, as this is placed in a laundry room and this is not the most convenient environment for such appliances!

Not sure I understand this fully, don't you have an ethernet cable tying router1 to router2? All am asking is, don't use router2 WAN port, plug this cable into a LAN port instead (the basis of converting router to access point). No WAN, no NAT, no second subnet.

If I misunderstand, plse post a diagram.

 

[bill001g]

Okay, I'll give it a try.
To be on the safe side, so I have to connect from LAN to WAN ports and assign the WAN port address outside the first router pool, while deactivating the DHCP on second router. This way the first router should act as DHCP for any clients on whatever router they're connected?

Won't work that way. The wan and lan must be on different subnets.

The DHCP requests will never make it to the primary router from the lan of the second router. This is a fundamental thing on how dhcp works. There is a way for dhcp to accomplish and use the primary router as the dhcp server but a consumer router does not support that feature.

 

[MacMarcus]

Thanks jsmithepa!
I did as you suggested and everything now works like a charm!
All I have done is moving the cable coming from router 1 LAN port, from WAN port to LAN port on router 2 where I disabled DHCP service, now everything is on the same subnet and the router 1 acts as DHCP server.
I can now access my resources from everywhere!
Thanks a million again!