How to connect Internet via a router?

myouch · 10-06-2005, 10:26 PM

It's Fedora core 2.

Everything used to be fine. My ISP doesn't support Linux, and I set up my router (linksys) under windows with Linksys CD. After I connected my linux machine to the router, it worked very well without any configuration.

My ISP sent me a new wirelss modem recently and I installed it, connected to router again. I could connect to Internet with my desktop Fedora, but it was not very stable. It took long time to resove the name sometimes. I installed the same Fedora in my laptop, and it could never connect to Internet, I couldn't activate ethernet connection either (eth0).

I decided to change back to my old modem. This time, Fedora in my desktop can't connect to Internet any more! Fedora in my laptop can't gain IP address either (can't activate the LAN connection)! My desktop always says it can't resolve the name. I set up as DHCP already.

Please help me!!! I need to do my project under linux urgently! Millions of thanks!

Some set up parameters;
DNS:
hostname: localhost.localdomain
primary DNS: 192.168.2.1
DNS search paht: no-domain-set.bellcanada

The device (eth0) is active in my desktop but it's inactive in my laptop. Both m desktop and laptop cannot connect to Internet. But the same configuration worked before.

(((

rylan76 · 10-07-2005, 01:11 AM

Hi

If you open an x-terminal on the two systems, and type in

netstat -r

do you get something like this:

Kernel IP routing table
Destination Gateway Genmask Flags MSS Window irtt Iface
169.254.255.0 * 255.255.255.0 U 0 0 0 eth0
169.254.0.0 * 255.255.0.0 U 0 0 0 eth0
default 169.254.255.100 0.0.0.0 UG 0 0 0 eth0

?

If you don't, that can be part of the problem. This line comes from my system - I also use a router to connect to the internet.

Most likely, you might find that the line with the "UG" in it is missing - this means that your kernel does not have a current "gateway" address to use when it must get packets off the internet for you, which might be why you cannot connect.

To add a gateway entry into the kernel routing tables, enter the following line in an x-terminal (I think you'll need to be root):

/sbin/route add default gw 169.254.255.100 netmask 0.0.0.0 eth0

Where you of course replace "169.254.255.100" with your router's address.

Don't know about DHCP, but you might try switching it off (erm... kill the DHCP process?) and configuring your /etc/resolv.conf file to contain the address of your ISP's DNS server.

Then, try to connect again to the net.

Hope this helped,

adz · 10-07-2005, 01:30 AM

Can you post the output fo dhclient eth0? You'll have to be root and post also what happens afterwards (ie can you access internet or not).

myouch · 10-07-2005, 07:36 PM

Thanks rylan76 and adz!

I did what you suggested. please see the following link.

I didn't know how to post my machine information when writing this last night. Pls go to see here for more information: http://www.linuxquestions.org/questi...hreadid=370786

adz · 10-07-2005, 09:27 PM

Well then can you post it now?

myouch · 10-07-2005, 09:35 PM

to adz:

Please click the link I gave above and see more information. Yes, I tried and got:

Code:

sit0: unkonw hardware address type 776
sit0: unknown hardware address type 776
Listening on LPF/eth0/00:0f:b0:72:c7:db
Sending on LPF/eth0/00:0f:b0:72:c7:db
Sending on Socket/fallback
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 4
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 4
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 10
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 12
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 16
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 9
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 6
No DHCPDISCOVER received
No working leases in persistent database - sleeping

I still can't connect to Internet.

adz · 10-07-2005, 10:47 PM

myouch · 10-07-2005, 10:59 PM

For all the nice persons reading this post:

Now the network situation is changed. I did nothing and the desktop can connect Internet suddenly. The laptop¡¯s eth0 can¡¯t be activated. It means that the router is good, the problem is in the laptop itself. You only need to concentrate on the information in the following link: http://www.linuxquestions.org/questi...hreadid=370490

Sorry I am new here and I don¡¯t know if I violate the rules here to say this. I just want to save your time. Thank you.