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I am a fresh network engineer and tasked with building a test bed to provide remote internet connectivity for users in remote areas.

I have no problems pinging the terminals located on both ends of the network but the remote terminal simply cannot connect to the Internet. Below is the diagram that I was following.

Remote PC ------Remote Router A ====== Remote Router B ----- Gateway (with Internet access)

---- is LAN and === wireless transmission

The leftmost network (remote) is 192.168.201.x/24

The network between router is 172.x.x.x/24

The rightmost network (Internet) is 192.168.200.x/24

It might be worth noting that the remote routers are more like modems with router capabilities. They only have one Ethernet port.

A PC connected to the gateway (it's a Linksys) via LAN can ping the remote PC. It can also ping any of the remote routers along the route. The same can be done from the remote PC's end.

However, when I try to ping a URL, for example google.com, using the remote PC, I will get the message that the name cannot be resolved.

I was wondering if anyone could give me some pointers on what is going wrong? I've been at it for weeks, and I'm running out of options to try.

Additional info: i tried pinging the ip address of google and it didn't work either. router is a satellite modem. remote PC is set to a static ip of 192.168.201.2/24. remote router A is 192.168.201.1/24. remote PC was configured with a DNS address (not 8.8.8.8 though)

setup diagram

Some elaboration regarding the image. Currently the setup is still being tested so the Tx and Rx ports of both Modem A and B are connected via cable.

The Linksys Gateway (Linksys 10/100 8 port VPN Router RV082) connects to the Internet through its WAN/Internet port. a total of 8 PCs can be connected to it to use the internet in this way.

Right now, I can ping from Remote PC to Modem A, Modem B, Linksys, Another PC. It fails when I ping to any IP on the Internet.

Remote PC has been configured with the same DNS settings as Another PC.


Routing Table of Modem A:

0.0.0.0/0 routed via BNC

Routing Table of Modem B:

192.168.201.0/24 routed via BNC

0.0.0.0/0 routed via ETH to 192.168.200.1

Routing Table of Linksys:

192.168.201.0/24 to use 192.168.200.200 as gateway

Linksys configuration

Device IP: 192.168.200.1/24

Device's connection to Internet is via static IP 147.25.x.x/24 with the gateway indicated as 147.25.100.1/24


I need to specify a next hop address for ETH on the Modem routes but not if the are using BNC because it is a point-to-point setup.

unfortunately, i can't share much about the linksys router as i have no access to the Internet facing side. i am only aware of the DNS server, default GW and the dynamic ip range.

Hope this is clearer.

  • What you appear to be missing is DNS. What DNS servers show on the PC? Can you ping the Google DNS by IP address instead of pinging the URL? – Ron Maupin Oct 14 '15 at 3:55
  • i tried pinging the ip address of google and it didn't work either. router is a satellite modem. remote PC is set to a static ip of 192.168.201.2/24. remote router A is 192.168.201.1/24. remote PC was configured with a DNS address (not 8.8.8.8 though) – cindy Oct 14 '15 at 5:27
  • Something is confusing about your drawing on Satellite Modem B. Satellite Modem A has the 172.x.x.x/24 network on the BNC connections, but Satellite Modem B does not. Having the Linksys model and configuration would help, too. – Ron Maupin Oct 15 '15 at 1:55
  • i have to admit i'm not too sure if Modem A's GW is set correctly. the config on the modem says that GW and IP are both for ETH. no configs necessary for BNC other than route tables. – cindy Oct 15 '15 at 2:07
  • Between each device, the addresses on the devices need to be in the same subnet. The Remote PC and Satellite A modem A interfaces need to be in the 192.168.201.0/24 subnet; the Satellite Modem A and Satellite Modem B interfaces need to be in the 172.x.x.x/24 subnet; the Satellite Modem B and Linksys interfaces need to be in the 192.168.200.0/24 subnet. – Ron Maupin Oct 15 '15 at 2:17
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From the remote PC, you ping all your routers but not an external IP, for example 8.8.8.8 (DNS google). Maybe you have forgotten a default route on one of your routers.

You can try to traceroute the IP 8.8.8.8 from the remote PC and see where your packet stops. If it stops, you can add a default route like 0.0.0.0 to the next router or gateway. If your packet stops on the gateway, your satellite connection maybe is not up or you have a problem with your satellite provider.

  • pinging from remote PC all the way to gateway is ok. i've yet to try tracert an ip address, though tracert a url will return with name cannot be resolved. i will see what i can do with the gateway but i wouldn't hold much hope because the current setup is just a testbed....so much of the gateway configurations are not within my control.... the ==== (wifi connection) is currently just a BNC cable connecting TX to RX of both modems – cindy Oct 14 '15 at 11:35
  • and what is the result of the traceroute to an external address? – Sorcha Oct 14 '15 at 11:38
  • i'll try it tmr once i get to work. too exhausted. thanks for the suggestion sorcha. – cindy Oct 14 '15 at 11:38
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based on your descriptions i guess you run some thing like that enter image description here

first of all i you must under stand that Router B has two type of connections , one of them between it and router A through satellite terminal with range of 172.x.x.x/24 and the another one between it and linksys which provide the internet. the way that make PC in site B access internet is NAT 192.168.200.x/24 range in the linksys router to its 147.25.x.x/24 IP.so you need to NAT 192.168.201.x/24 to this IP as well.

guiding notes

1- try to ping the 192.168.200.1 from PC in site A
2- check the configuration done for 192.168.200.x/24 to access internet through linksys and do it same for 192.168.201.x/24

  • hi Gadeliow, the diagram is mostly correct except that both Router A and Router B are satellite terminals. the connection to the Internet is via a linksys gateway/router i.e. i actually have 3 "routers" in the network. i'll see if i can draw up a diagram to illustrate it better. will try out your notes and see how it goes. thanks! – cindy Oct 14 '15 at 23:19
  • I'll modern my draw and my answer – Gadeliow Oct 15 '15 at 5:14
  • 1. ping is through. 2. will have to take a look. so far even with matching configs, it doesn't go thru. thanks for the effort! appreciate it – cindy Oct 15 '15 at 23:57
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Based on the little information you have provided (no router models and no configurations, especially PC DNS configuration), it appears you have a DNS problem.

If you can ping an Internet IP address (e.g. 8.8.8.8), but not ping by URL, you have a DNS problem; the PC cannot resolve the name because it doesn't have a DNS server with Internet DNS names.

  • i tried pinging the ip address of google and it didn't work either. router is a satellite modem. remote PC is set to a static ip of 192.168.201.2/24. remote router A is 192.168.201.1/24. remote PC was configured with a DNS address (not 8.8.8.8 though) – cindy Oct 14 '15 at 5:25
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The issue may be that the Internet Gateway (linksys) router does perform NAT/PAT for the 192.168.200.0/24 network but not for the the 192.168.201.0/24 network.

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