Wireless fedora computer cannot access internet (but can access network)

eric_x · #1 16th July 2005, 10:44 PM

Recently, I installed FC4 on an old Compaq Presairo 1200z. Everything setup fine, except internet. First of all, it didn't recognise the built-in lan card, so I could not get internet through hard-wiring. But that is not my problem, because it is a laptop, and I wanted wireless internet anyways. So I used the linksys WPC11 v.3 wireless network card to try to access the internet (which had worked with windows installed). The card was recognised by fedora, and I configured it with my wireless network (encription/wep off), but still, no internet. I did ifconfig or iwconfig, and I had an assigned IP address (as the routers use DHCP). In fact, I could access the routers and computers on my network fine, that is, anything 192.168.1.x. I successfuly setup two windows computers on the same wireless network, with no problems. So, I don't think that the problem is with the router, I think it has something to do with the network card. Any help would be appreciated. If you need any more information, ask, and I will answer ASAP.

pieter · #2 16th July 2005, 10:58 PM

You say you have connection to devices in your own subnet but not to the internet (e.g. you can ping your internetrouter from your laptop).

It probably means that your card is ok but that your default gateway is not correctly configured. If you use static address (ifconfig) instead of dhcp (dhclient) then this is very likely.

Check your default gateway settings on your laptop: #route
If not correctly then add one with: #route add default gw x.x.x.x with x.x.x.x pointing to your internet-router.

If that is all ok then you could also check your subnetmask on your notebook
good luck!

eric_x · #3 16th July 2005, 11:14 PM

This is what I get for the #route command:

[eric@localhost ~]$ /sbin/route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.1.0 * 255.255.255.0 U 0 0 0 eth0
169.254.0.0 * 255.255.0.0 U 0 0 0 eth0
default 192.168.1.1 0.0.0.0 UG 0 0 0 eth0

The default gateway looks right, but the subnet mask ( subnet mask = genmask ?) should be 255.255.255.0, I think. I don't know how to change that though.

pieter · #4 16th July 2005, 11:28 PM

Eric,

Your routing table looks ok. The mask is 0.0.0.0 is because 192.168.1.1 it is a host-address (thats normal). (And I suppose 192.168.1.1 is your router to the internet. )

You can still check your subnetmask from your laptop (ifconfig eth0). It should be 255.255.255.0.

What is the ping reply if you ping to an outside host?
Or try a traceroute

eric_x · #5 16th July 2005, 11:35 PM

The subnet mask checks out to be ok with ifconfig, but when I try to ping or traceroute www.google.com, it says "unknown host"

edit: I have a slightly abnormal network, so I have included a crude scetch of the network. I dont think that the network is the problem, but anything is possible. Also, I am accessing the internet through two routers (or a router and a gateway), but once I set the second router up, I had no problem accessing the internet with windows, wirelessly or not.

pieter · #6 16th July 2005, 11:45 PM

Unknown host means probably a DNS problem.
You can ping succesfully by ip address (ping 216.239.59.104) ?

Check /etc/resolv.conf It should have "nameserver 192.168.1.1" (without #

)or some other address pointing to your nameserver.

eric_x · #7 16th July 2005, 11:51 PM

Pinging 216.239.59.104 works. By the way, how do you ping, like, 3 times, instead of pinging forever?

Also, the only thing in resolv.conf is "search localdomain". Should I replace that with nameserver 192.168.1.1?

pieter · #8 16th July 2005, 11:54 PM

ping -c 3 x.x.x.x
yes you should replace that line, it is probably the cause.

eric_x · #9 17th July 2005, 12:02 AM

That fixed it! I can now ping, access the internet, and update the computer! Thanks for your help, I would have never been able to fix the computer otherwise.

AlmereLinux · #10 23rd July 2005, 11:18 AM

Pieter,

I had similar problems, your step by step answers helped to solve my networkproblems as well. Thank you very much.

gking2224 · #11 11th April 2006, 11:47 PM

Ditto - I had exactly the same situation and this thread helped enormously. Thanks!!

One extra thing I found was that editing /etc/resolv.conf to include 'nameserver <ip.of.router>' didn't solve the nslookup problem. Consequently, I could only get it to work by enabling DHCP, rather than static IP address.

The solution for me was to add the following to the Route tab of the configuration of my wireless device in Network Configuration:
Destination Network Prefix(Netmask) Gateway
0.0.0.0 0.0.0.0 <ip.of.router>

Oh, and I have to disable my wired lan from activating on bootup, as even though it's not connected it still tries to use that in preference to my wireless adapter.

gummybearx · #12 12th April 2006, 03:11 PM

i have a problem similar to this, but i have wlan0 and eth0 and the comp keeps trying to look for the internet through eth0, but wlan0 is where it should be looking. when i ping 192.168.1.1, it tries to ping MY router, which is hooked up to the eth0, and not the remote router(diff router connected to wlan0)
when eth0 is disabled i can see the router that i want(the wirreless)

and i cant disable eth0 because it is a headless server and i have to ssh into through hy local router on eth0

but my ne3twork looks very similar to the pic above

any suggestions would be fantabulous

gking2224 · #13 12th April 2006, 03:17 PM

You should be able to stop eth0 from activating at boot-time by editing
/etc/sysconfig/network-scripts/ifcfg-eth0
and setting ONBOOT=no

and deactivate eth0 now by typing: ifdown eth0

from <a href="http://www.linuxheadquarters.com/howto/networking/networkconfig.shtml">here</a> and <a href="http://www.siliconvalleyccie.com/linux-hn/network-linux.htm">here</a>

gummybearx · #14 12th April 2006, 08:22 PM

yeah but i need both up so i can ssh into it and route the signal from wlan0 to eth0 and out

dshaw256 · #15 13th April 2006, 01:13 AM

Quote:

Originally Posted by gking2224

One extra thing I found was that editing /etc/resolv.conf to include 'nameserver <ip.of.router>' didn't solve the nslookup problem. Consequently, I could only get it to work by enabling DHCP, rather than static IP address.

The solution for me was to add the following to the Route tab of the configuration of my wireless device in Network Configuration:
Destination Network Prefix(Netmask) Gateway
0.0.0.0 0.0.0.0 <ip.of.router>

It looks to me like you had two problems going. Once you got your name server right, you ran into the lack of a default route to the internet. You need both.

Dave