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I recently bought a Cisco RV130W router and plan to use it as a secondary router in a cascaded router setup. I want to do this so I can isolate my own devices (NAS, printer, PC, Laptop) and prevent them from being accesible by anyone on the primary network. Also I'd like to use static IPs for my devices.
My (secondary) routers WAN-port is plugged into the primary (internet-facing) routers LAN-port via a switch. The primary routers WAN-port is where the internet comes from. It is a FRITZ!Box 7430, a very common brand in Germany.

I wasn't expecting everything to work right out of the box, but I honestly didn't expect this much trouble either. Various tutorials made this seem rather easy. The router itself DOES have internet access and was able to pull the newest firmware version from the Cisco site as well as traceroute Google with the built in feature on the web interface. All devices on my network are able to talk to each other (e.g. I can print with my PC), but for some reason I'm not able to reach the internet from any of my devices.

My question should be obvious: how can I access the internet from the devices connected to the secondary router?


I already did a couple hours of Google searches yesterday, but nothing could really help me. So far I have only attempted the following:

  • set mode from "gateway" to "router" (which disables NAT)
  • activated RIP

Admittedly, I've tried nothing and I'm all out of ideas.

I suspect that either the routing or something related to IPv6 might be off, but to me the routing table looks fine at first glance. Then again I've never dealt with anything like this before and this is literally my first experience with setting up a router this way. I think it's best to just post the table here:

IPv4:

Destination LAN IP  Subnet Mask     Gateway             Interface 
192.168.178.0       255.255.255.0   192.168.178.164     WAN 
192.168.1.0         255.255.255.0   192.168.1.1         LAN 
0.0.0.0             0.0.0.0         192.168.178.1       WAN

IPv6:

Destination                                 Next Hop                    Interface    
2003:d4:bf20:bd00::/64                      ::                          WAN 
2003:d4:bf20:bd00::/64                      ::                          WAN 
fe80::/64                                   ::                          LAN 
fe80::/64                                   ::                          WAN 
fe80::/64                                   ::                          WAN 
fec0::/64                                   ::                          LAN 
::/0                                        fe80::cece:1eff:fefd:b52f   WAN 
::1/128                                     ::                          lo  
2003:d4:bf20:bd00::/128                     ::                          lo  
2003:d4:bf20:bd00:72f3:5aff:fe75:47f7/128   ::                          lo  
fe80::/128                                  ::                          lo  
fe80::/128                                  ::                          lo  
fe80::/128                                  ::                          lo  
fe80::/128                                  ::                          lo  
fe80::/128                                  ::                          lo  
fe80::/128                                  ::                          lo  
fe80::/128                                  ::                          lo  
fe80::/128                                  ::                          lo  
fe80::f3:5aff:fe75:47f9/128                 ::                          lo  
fe80::f3:5aff:fe75:47fa/128                 ::                          lo  
fe80::f3:5aff:fe75:47fb/128                 ::                          lo  
fe80::211:22ff:fe33:5511/128                ::                          lo  
fe80::72f3:5aff:fe75:47f6/128               ::                          lo  
fe80::72f3:5aff:fe75:47f6/128               ::                          lo  
fe80::72f3:5aff:fe75:47f7/128               ::                          lo  
fe80::72f3:5aff:fe75:47f8/128               ::                          lo  
fec0::/128                                  ::                          lo  
fec0::1/128                                 ::                          lo  
ff02::1/128                                 ff02::1                     LAN 
ff02::1/128                                 ff02::1                     WAN 
ff02::2/128                                 ff02::2                     LAN 
ff02::16/128                                ff02::16                    WAN 
ff02::fb/128                                ff02::fb                    WAN 
ff02::1:ff09:8002/128                       ff02::1:ff09:8002           WAN 
ff02::1:ff5a:f980/128                       ff02::1:ff5a:f980           WAN 
ff02::1:ff75:47f6/128                       ff02::1:ff75:47f6           LAN 
ff02::1:ffa2:dcc1/128                       ff02::1:ffa2:dcc1           WAN 
ff02::1:ffb6:f89b/128                       ff02::1:ffb6:f89b           WAN 
ff02::1:ffc1:5152/128                       ff02::1:ffc1:5152           WAN 
ff00::/8                                    ::                          LAN 
ff00::/8                                    ::                          WAN 
ff00::/8                                    ::                          WAN

Some background info/context: I live in a fraternity with ten other people. Everyone is connected to the internet through a single (primary) router. The situation is quite messy, since this poor router has to handle WiFi for approximately 20-40 devices at any given time (we get a lot of house guests). WiFi is unusably slow and unstable. But worse than that: the combination of static IPs and DHCP means I'm not able to run my NAS without daily address conflicts. Also I fear people might eventually figure out how to print on my network printer.

1 Answer 1

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First, consider what is plugged where.

  • If the two routers' WAN ports are plugged into a switch, which then is connected to the internet, then they are not cascaded but are discrete devices visible to your ISP, which may limit the connection to one device.

  • If the downstream router's WAN port is plugged into one of the upstream router's LAN ports (directly or through a switch), then the downstream router is cascaded and so is just another device on the upstream router's subnet/LAN, invisible to the ISP because of the upstream router's firewall/NAT. This is the correct configuration.

Second, check whether the downstream router's WAN port has an IP address on the upstream router's subnet/LAN. So, either (a) verify that the upstream router has DHCP enabled (so that it can assign IP addresses) and that the downstream router's WAN port is configured as a DHCP client (i.e., to get its IP address automatically); or (b) configure the downstream router's WAN port with a static IP address on the upstream router's subnet/LAN.

It sounds as if the upstream router has DCHP enabled, so the trick here is likely just configuring the downstream router's WAN port.

It also will help to specify DNS servers in configuring the downstream router. Google's often are recommended: 8.8.8.8 and 8.8.4.4.

Third, if you want to prevent outside access to the downstream router's subnet/LAN, the downstream router should be configured as a gateway with NAT (i.e., the firewall) enabled. Then, if your NAS and network printer are configured to be behind the downstream router's firewall with IP addresses on its private subnet/LAN, they shouldn't be accessible from outside. If NAT is disabled, then the downstream router is just a bridge/switch (same thing) and all the devices connected to it are fully visible to other devices on the upstream router's subnet/LAN. So, enable NAT on the downstream router and configure it as a gateway.

Also, you will save yourself much time and tinkering if you skip static IP addresses on your subnet and enable DHCP on the downstream router instead. Then, all you need is to configure each device to be on the correct network.

Remember that because the downstream router will be just another device on the upstream router's subnet/LAN, it will have the same issues in getting outside internet access. That is a separate problem suggesting capacity constraints, but you can test whether you have solved your LAN set-up problems by opening a command prompt (in Windows) or a terminal (in Linux) and pinging a popular web site, e.g., in Windows,

ping www.cnn.com

or in Linux,

ping -c 4 www.cnn.com

Avoid IPv6 altogether because it adds unnecessary complexity for your configuration. IPv4 is more than adequate and far simpler. In fact, disable or firewall IPv6 completely if possible.

Also, in my experience, no reason exists for you to have RIP enabled but you can tinker with that to see what works best.

Good luck!

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