when connection to a network the following error massage shown (unable to determine IP information for eth0. link not present)

and about the internet it said that the host not found

im using an Ethernet cable
any solution please?

Hi, welcome to LQ forums.

Your problem is most likely faulty or not connected LAN cable, or switch (link not present).

i make sure the the cable is connected but still the problem is there

if this is Red hat RHEL 5.5 then please use your paid for tech support
if you have any missing software then you can only get it from red hat and for that you need to pay.

or install something else . Like CentOS 5.5

Have you verified that the switch side is working? A simple way to test this is to take the LAN cable and plug into another machine (your laptop for example) and try to get networking to work.

This would eliminate the possibility of a problem on the network side - and thus you know its a configuration problem on the OS side.

"Link Not Present" means that there is no active Layer 1 link between your machine and its switch (layer 1 = physical link). "Host not found" is a result of "Link Not Present"- you won't be able to find a host on the Internet if you don't have DNS or network services.

I would check these things:

1) Are you using a straight-through ethernet cable?
2) Does this cable work on another machine?
3) Do the LED's light up on both the ethernet card and switch when you plug the cable in between them?

If the cable is confirmed to work, and LED's light up on both ends, then try bringing the interface back into service.

Also if you run the command:
Does your ethernet interface show up at all?

If you do not get any link LED's lighting up, then run the command:
See what it reports for your NIC driver.

If these steps don't work I would start inspecting your network hardware.