I am trying to connect two computers in my dorms. One is a desktop that is wired connected. The other is a laptop that is wireless connected. Both computer browse the internet with no problems. Both can ping themselves. The problem is that I cannot ping each other. I know it is not a firewall issue because if I connect the laptop with an Ethernet cable there is no problem.

I know it must be a network configuration but I do not know what to do. I have already read all I could find.

thanks,

Is the wireless network from your router?

Nope. The LAN is in a dorm at a college. I do not have access to the router. What I find strange is that I can ping computers connected to the Ethernet port but I cannot using the wireless although I can surf the internet in both of them. In some post it was suggested that it was a communication problem from the laptop and that the Eth0 interfaces should be disabled but how???

Try a traceroute with the wired connection, then with the wireless one, and try to identify where it fails. That might provide some hints.

I'm sorry. My experience with networks is very basic... how exactly I do the traceroute? thanks...

traceroute [ip address], e.g. traceroute xxx.xxx.xxx.xxx

traceroute [domain]. e.g. traceroute google.com.

See man traceroute for more.

Traceroute give me same result than ping... it cannot connect :/


traceroute to 10.88.8.6 (10.88.8.6), 30 hops max, 60 byte packets
1 * * *
2 * * *
3 * * *
4 * * *
5 * * *
6 * * *
7 * * *
8 * * *
9 * * *
10 * * *
11 * * *
12 * * *
13 * * *
14 * * *
15 * * *
16 * * *
17 * * *
18 * * *
19 * * *
20 * * *
21 * * *
22 * * *
23 * * *
24 * * *
25 * * *
26 * * *
27 * * *
28 * * *
29 * * *
30 * * *

I am almost sure that there is a problem with the wireless configuration...

---------- Post added 04-16-12 at 02:38 AM ----------

btw I can do traceroute to localhost and external servers...

The wired and wireless networks may be isolated or have a natted router betweenthem (such as for the dorm). If your wireless has an IP address, and you are accessing websites, the device is working. Are you joining the right wireless network? Can others access hosts on the LAN side via wireless access?

"Both computer browse the internet with no problems"

There was no reason to do ping after this statement. What could you prove? Ping is a very old simple test that tends to be blocked more and more.

Going back to your original post:

Did you try the traceroute with a wired connection (though at this point is would seem not to matter, since the intervening devices seem to be set not to provide meaningful replies)? My thought was to compare the two to try to get a hint, since you indicated the wired connection was working.

thanks for your replies...

jschiwal: yes, I assume there is some isolation in the network between the wireless and the wired computers. However both computers present the same external IP which means that they are in the same NAT network... am I right?

jefro: I find strange that I can ping external servers and not the one in the supposedly same network. I could have use any other type of communication but ping seem more simple... I didn't know it was in disuse. My experience with networks is very limited.

frankbell: tracroute from the wired PC to the laptop give no result...

Is this such an uncommon occurrence?

Useless test.


It is blocked by some means.

Thanks Jefro, that was really useful. But what I need really is to know how can I bypass that block...

Yes, it means they are both behind a NAT. It also means that you will only be able to connect them by changing firewall configurations.

Please post the IP addresses and gateway addresses for both computers. I'm guessing that the wired and wireless networks are on different subnets. The router at the gateway may provide NAT masquerading for both networks but not route traffic between the two. You may need to use a wireless or wired router yourself or connect the two computer via crossover cable to be able to shares files over the network.