I'm running Ubuntu 7.04 on a Dell Inspiron 5100. I'm connected to a Linksys Wireless(ed) Router via ethernet. The laptop *thinks* it's connected, because when I disconnect the ethernet cable a little popup on Ubuntu's status bar notifies me of the disconnection; however, my laptop does NOT show up on my router's DHCP table. It's like the laptop is never requesting one? I'm not sure.

Try to run, from a terminal emulator, this command:
if eth0 is not your ethernet device (it's usually eth0 for wired, eth1 or wifi0 for wireless, but may be different); I'm fairly sure Ubuntu uses dhclient and not dhcpcd, but you can try both. Probably you need to be root, so use sudo if needed.

If that brings you an ip address etc. then the problem is that dhcp request is not made. If that doesn't work, then it's something with your NIC not working all right -- maybe drivers?

Although I don't know how to set a static IP for your computer in Ubuntu (used a USB port to connect an old laptop, new laptop is still running XP), this may also be a solution. It also gives you better control over certain applications. Like me: I use a few P2P-programs, and they don't work well with uPnP, so I had to set a static IP-adress for my computer. Just be sure to set two IP-adresses; one for WiFi, and one for Ethernet, as ONE IP-adress on both may cause a "crash" in the router.

I imagine this is no worse in Ubuntu than in Windows. But check out the IP-adresses for subnet mask (generally 255.255.255.x) and standard gateway (usually your router's IP-adress). You also need to get the numbers for DNS-server. This is two IP-adresses that connects to your ISP.

When this is done, you choose a static IP. Since it is a private IP, known only to the router, I can tell you that mine are 192.168.0.146 (WiFi) and 192.168.0.147 (Ethernet). With a static (private) IP, you can also forward ports for programs, giving them a sure way through your router, should the need arise.

As I haven't had your problem, I wouldn't know if b0uncer's suggestion is the correct one.

I can tell you that if you set a static IP, no DHCP request is made to the router, as it is always the same. (You may have to disable DHCP in the router)

Well, that's my two (OK, four) cents on the matter.

Thank you for the responses.

$ dhclient eth0 (eth0 is my wired connection)

after it seemed to loop through possibilities, it returned
No DHCPOFFERS received
No working leases in persistent database - sleeping.



Ok weird...

I thought I'd try dhclient on my wireless after entering the ssid & key,
After entering that, the wired connection started to work. There was a good 5 min between these attempts so the wired connect did have enough time. Definitely weird, I may be back when my lease dhcp lease expires!

Thanks again for the help!

Frids Plz Help! I Have Installed Ubuntu 8.04 Lts Desktop Edition In The "f" Drive Of Windows...hence Both Os Runs For Me! But Im Unable To Connect To The Internet....plz Help...mine's Is A Airtel Broadband Adsl2+ Modem

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