Configuring some routes on some PCs

[riahc3]

To make things a lot more simple, I have this:

1 router, 1 switch, 4 PCs (with several NICs)

A can ping B and C (reverse also true)
C can ping A, B, and D (reverse also true)

How do I configure so that A and B can ping D and D can ping A and B? I cannot change any IP and not touching the router.

My logical idea would be to set up a route. How do I do this on A and B?

Thank you

 

[RadiclDreamer]

You will need to create a sub interface on the router port to be in the same subnet as the 172.16.0.0/16 network and enable routing. What device are you running as a router?

 

[riahc3]

You will need to create a sub interface on the router port to be in the same subnet as the 172.16.0.0/16 network and enable routing. What device are you running as a router?

Like I mentioned, I cannot touch the router. At best, I can use A as another router if I need to set up some routes that pass thru one place. I rather not do that but...

 

[seepy83]

If C and D are actually connected directly, like you have in the map, then C will need to be acting as a Router. If C is a Windows box, then it would need to be a Server OS and running RRAS to route traffic between 192.168.100.0/24 and 172.16.0.0/16. Then (again, assuming that A and B are Windows boxes), you can use the Route Add command to enter the new route into the routing table (so that traffic for the 172.16.0.0/16 network is sent to C instead of to the Default Gateway).

 

[drebo]

Quit your job. Please, for the love of all that is good and holy, find a new career.

Please, no personal attacks in the technical forums.
-Admin DrPizza

 

[riahc3]

If C and D are actually connected directly, like you have in the map, then C will need to be acting as a Router. If C is a Windows box, then it would need to be a Server OS and running RRAS to route traffic between 192.168.100.0/24 and 172.16.0.0/16. Then (again, assuming that A and B are Windows boxes), you can use the Route Add command to enter the new route into the routing table (so that traffic for the 172.16.0.0/16 network is sent to C instead of to the Default Gateway).

C is running WES7 (Windows 7) and D is running Windows CE. C has Routing and Remote Access services DISABLED AND STOP. Yet, I can perfectly ping 192.168.100.100 and 172.16.9.10 from C. D can ping C.

A is a Linux box and B is a Windows box. I don't know if that was important to state or not.

The only real scenario about something being a router would be A.

 

[riahc3]

Quit your job. Please, for the love of all that is good and holy, find a new career.

Well, since you understand your job and career perfectly, I imagine this is a breeze in the park for you so please, enlighten us.

 

[seepy83]

C is running WES7 (Windows 7) and D is running Windows CE. C has Routing and Remote Access services DISABLED AND STOP. Yet, I can perfectly ping 192.168.100.100 and 172.16.9.10 from C. D can ping C.

Of course you can ping those networks from C. They're directly connected.
Of course D can ping C. It's directly connected.

A and B won't be able to ping D unless C is performing Routing

This is network/OSI Model basics.

You have to learn the basics before you try to design a network. Even something as simple as what you mapped out.

 

[Squeetard]

Bridge the nics on C.
Edit: This is by no means a best practice. But if you can't touch the router or don't have a managed switch then I don't see another way.

 

[riahc3]

Of course you can ping those networks from C. They're directly connected.
Of course D can ping C. It's directly connected.

I read:

"If C and D are actually connected directly, like you have in the map, then C will need to be acting as a Router"

So I thought you ment that C would have to be acting as a router to actually communicate between C and D! I was surprised to read that.

A and B won't be able to ping D unless C is performing Routing

This is network/OSI Model basics.

You have to learn the basics before you try to design a network. Even something as simple as what you mapped out.

Claiming that unless C is performing routing is what is unclear to me.

If in B I issue

"Make a route using 192.168.100.169 when trying to connect to 172.168.9.1"

I don't see why when I try to ping 172.168.9.1 from 192.168.100.73, it doesn't use 192.168.100.169 to get to 172.168.9.1 since I state it to use 192.168.100.169 and 192.168.100.169 knows how to get to 172.168.9.1

Maybe that's what Im missing and its something obvious that I haven't realized.

On the WES7, I enable RRAS if needed but it is at the end of the day, still a client OS....

 

[Squeetard]

I read:

"If C and D are actually connected directly, like you have in the map, then C will need to be acting as a Router"

Bridge the nics on C.

This will make C act as a router.

 

[riahc3]

I bridged the NIC with 192.168.100.169 and the NIC with 172.16.9.1 and it did nothing to solve the issue.

 

[RadiclDreamer]

I dont recommend bridging, I also dont recommend adding routes on non network equipment. If you can't touch the router you are setting yourself up for issues down the road when these things fail. Im not telling you it CANT be done the way you want, but I am saying it SHOULDNT be done that way

 

[riahc3]

I dont recommend bridging, I also dont recommend adding routes on non network equipment. If you can't touch the router you are setting yourself up for issues down the road when these things fail. Im not telling you it CANT be done the way you want, but I am saying it SHOULDNT be done that way

Yes, I understand that using a client PC to route isn't the most recommended thing in the world but I want to do it to

1: Learn something new (always a good thing even if it is noncommon)
2: I believe since I do not have access to the bottom router, it is the only way to do this.

 

[riahc3]

So any help on setting C up as a router to route the IP address of D to the rest of the network?

 

[kevnich2]

Is this your home network or is this a production work network? If it's your production work network, go see your network admin or your boss and explain what you want to do and why.

 

[alkemyst]

OP, is there a reason you cannot talk to who has access to that router? If you have simply lost the password, there are recovery methods.

Setting up secondary routing on a PC would be a big cludge in my opinion and if this is for a work environment; the kind of thing that could get someone terminated for far outside even acceptable practices.

 

[Elixer]

If C & D are linux, you should be able to use IPTABLES to do what you want...

 

[riahc3]

OP, is there a reason you cannot talk to who has access to that router? If you have simply lost the password, there are recovery methods.

Setting up secondary routing on a PC would be a big cludge in my opinion and if this is for a work environment; the kind of thing that could get someone terminated for far outside even acceptable practices.

I cannot do anything to that bottom router because

1: Its not my company
2: Its offsite

And yes, Ive actually tried to talk to IT on the other company's side but either they dont have anyone (laughable) or the IT is too tight up to be interested in helping.

 

[riahc3]

If C & D are linux, you should be able to use IPTABLES to do what you want...

C WAS Linux......now its Windows.

 

[kevnich2]

If they are all on the same vlan/broadcast domain (highly likely unless c and d have a dedicated cable going between the NIC's), change d so they are all in the 192.168.100.x subnet and eliminate second NIC from C. Problem solved.

If you cannot change an IP - please tell us why you can't or aren't allowed to change any IP?

 

[Elixer]

I think there is something missing here, it almost looks like whomever set this up wanted access control for whatever reason. If that is the case, has something changed between now and before ?

For all we know, D could be mission critical, and that is why A & B were setup the way they were.

 

[kevnich2]

I think there is something missing here, it almost looks like whomever set this up wanted access control for whatever reason. If that is the case, has something changed between now and before ?

For all we know, D could be mission critical, and that is why A & B were setup the way they were.

I agree - the OP is leaving out a lot of detail as far as how it's currently setup and why and why exactly he wants things changed. This obviously isn't his home network so I wouldn't expect much help in changing things unless he gives more specific information as far as why it's setup how it is currently and why he actually wants to change it.

 

[seepy83]

OP had another thread (here http://forums.anandtech.com/showthread.php?t=2387705) before this one started where he was saying that the "C" machine in this thread used to be some little Linux router (http://www.netmodule.com/products/industrial-routers/wireline-router.html), and everything worked fine before they swapped that out for a Windows Embedded 7 PC and tried to build the same network. It's all very vague, but basically it sounds like he had a device that was handling routing and VPN termination, and he's trying to replace it with a Win7 box. That's why my recommendation was that if he needs to use a Windows box, then it's probably going to need to be Windows Server running RRAS.