Configuring some routes on some PCs

[riahc3]

I have the following:

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

 

[bill001g]

Routes will do you no good since all these ip are likely in the same subnet. You have some subnet mask configured wrong or you have something strange with your cabling. You can really only use a single nic card on each machine without very special configuration

I would be suspect of machine D. If all the subnet masks are the same and you have no duplicate ip addresses then I would be looking for firewall filters preventing the traffic.

 

[plivin89]

try this on a and b
route add 172.16.9.0 mask 255.255.0.0 192.168.100.169

and on D

route add 192.168.100.0 255.255.255.0 172.16.9.1

I am guessing C already has the route to the locations in its arp so you could maybe treat it like a router

 

[riahc3]

Routes will do you no good since all these ip are likely in the same subnet. You have some subnet mask configured wrong or you have something strange with your cabling. You can really only use a single nic card on each machine without very special configuration

I would be suspect of machine D. If all the subnet masks are the same and you have no duplicate ip addresses then I would be looking for firewall filters preventing the traffic

This is the configuration.

And I can use only one nic on each machine? What? I can have as many physical NICs I want. The metrics of each network is a a completely different story.

And I mentioned: I cannot change the configuration. I can only add/modify/delete routes on A, B, C, and D.

 

[riahc3]

try this on a and b
route add 172.16.9.0 mask 255.255.0.0 192.168.100.169

and on D

route add 192.168.100.0 255.255.255.0 172.16.9.1

I am guessing C already has the route to the locations in its arp so you could maybe treat it like a router

I tried this but nothing....

The best thing I can use as a router is A...

 

[bill001g]

Where did these IP come form I saw nothing in the post.

You can not have multiple nics on the same subnet. If you use different subnet on your nics you need a switch that can support vlans or mutliple separate switches. You also need a real router not the consumer gateway things to route between subnets.

If you have just cabled up a bunch of nics to a dumb switch and just started assigning different ip and subnet masks you are very likley to get results like you have.

You need to go back and start with a proper design......why you can ONLY add route commands and nothing else almost makes this appear to be some homework assignment rather than a real issue.

 

[plivin89]

is this a real world issue or an assignment ? you could config vlans between to two subnet like what bill suggested then configure "router on a stick" with the router so they can communicate.