Cannot acquire DHCP IP address from router

dwhitney67 · 10-31-2007, 02:39 PM

Hello,

I have attempting without success to setup a DHCP client on a CLFS distro. I piggy-backed on an existing thread in the LFS forum, but it appears that it is not getting much visibility, and thus the reason for this new post.

Here's the situation... when I run "/etc/sysconfig/ifup eth0" all I get is the following output:

Code:

Bringing up the eth0 interface...
Starting dhclient on the eth0 interface...
Internet Systems Consortium DHCP Client V3.0.5
[snip]
Listening on LPF/eth0/00:30:59:02:42:ea
Sending on   LPF/eth0/00:30:59:02:42:ea
Sending on   Socket/fallback
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 5
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 6
No DHCPOFFERS received.
Unable to obtain a lease on the first try.  Exiting.

The /etc/sysconfig/ifconfig.eth0/dhcpcd file looks like:

Code:

ONBOOT="no"
SERVICE="dhclient"
DHCP_START="-1"
DHCP_STOP="-q -r"
PRINTIP="no"
PRINTALL="no"

The /etc/dhclient.conf file looks like:

Code:

timeout 10;
interface eth0{
prepend domain-name-servers 127.0.0.1;
request subnet-mask, broadcast-address, time-offset, routers,
        domain-name, domain-name-servers, host-name;
require subnet-mask, domain-name-server;
}

When I run "ifconfig eth0":

Code:

eth0        Link encap:Ethernet  HWaddr 00:30:59:02:42:EA
            UP BROADCAST MULTICAST MTU:1500 Metric:1
            [snip]
            Interrupt:5

When I run "lspci | grep -i ethernet":

Code:

00:12.0 Ethernet controller: Intel Corporation 8255xER/82551IT Fast Ethernet Controller (rev 10)

When I run "dmesg | grep eth0":

Code:

eth0: OEM i82557/i82558 10/100 Ethernet, 00:30:59:02:42:EA, IRQ 5.

When I run "lsmod":

Code:

Module             Size  Used by
eepro100          23824  0
mii                4224  1 eepro100
evdev              6912  0
apm               15468  0
rtc                8628  0

With all of this information, can someone tell me why I cannot acquire an IP address from the Linksys router? All of my other systems (Ubuntu, Fedora Core 5, Fedora 7) work fine on my LAN, as does the actual cable running to the non-working system.

Please... I need help sorting out this issue.

bigrigdriver · 10-31-2007, 04:22 PM

Quote:

00:12.0 Ethernet controller: Intel Corporation 8255xER/82551IT Fast Ethernet Controller (rev 10)

Can you determine which kernel module is required for the ethernet controller, and whether or not that module is currently loaded.

I think this

Quote:

eth0 to 255.255.255.255

refers to local network or local host, something of the sort. You aren't getting past your firewall (if you have one) to the outside world. And, without the module refered to above, you won't.

The_JinJ · 10-31-2007, 04:26 PM

Does it work with a static IP assigned?

dwhitney67 · 10-31-2007, 05:52 PM

Yes, I tried using a static IP address before, by creating within /etc/sysconfig/ifconfig.eth0 a file using these instructions:

Code:

cd /etc/sysconfig/network-devices &&
mkdir -v ifconfig.eth0 &&
cat > ifconfig.eth0/ipv4 << "EOF"
ONBOOT=yes
SERVICE=ipv4-static
IP=192.168.1.1
GATEWAY=192.168.1.2
PREFIX=24
BROADCAST=192.168.1.255
EOF

Still no joy with getting the networking up and running. Anyhow, I went back to my attempts to use DHCP because ultimately I must have a DHCP capable system/OS.

When I tried to "force" settings onto the eth0 interface using ifconfig, I still was not able to ping my router. I used a statement similar to the following:

Code:

# ifconfig eth0 192.168.1.107 netmask 255.255.255.0 broadcase 192.168.1.255

What I cannot do is to get the eth0 to "run", or in other words have ifconfig display that it is RUNNING.

bigrigdriver-

What module are you referring to? The ethernet adapter I have requires the 'eepro100' kernel module, which is loaded (see my lsmod output). However, I cannot be certain that is being used by any service. How can I verify that it is?

dwhitney67 · 11-01-2007, 01:40 PM

I still cannot get the network setup on my system. Can someone please help?

seelenbild28 · 11-01-2007, 08:20 PM

are you sure that your router is working? perhaps it does really not offer dhcp? perhaps some misconfiguring?

dwhitney67 · 11-02-2007, 06:59 AM

The router, a Linksys WRT54G, is working just fine. I use both wired and wifi setups for my other systems. The system for which I am seeking help to configure is using a wired-connection... and yes, the CAT-5 cable it uses is fine.

seelenbild28 · 11-02-2007, 09:07 AM

I only found this thread in LX:

http://www.linuxquestions.org/questi...oot-up-563550/

but since your module is loaded and working for other distros I don't know what could be problem besides the distro itself....

and sorry, yes you know that thread!*g google does not help much... hmm..

dwhitney67 · 11-02-2007, 11:47 AM

I've been through the thread you posted. In fact, you may have noticed that I posted a query at the very end of it... of course, never getting a response. I was hoping the OP of that thread could help me.

lleb · 11-02-2007, 12:56 PM

Quote:

Originally Posted by dwhitney67

Yes, I tried using a static IP address before, by creating within /etc/sysconfig/ifconfig.eth0 a file using these instructions:

Code:

cd /etc/sysconfig/network-devices &&
mkdir -v ifconfig.eth0 &&
cat > ifconfig.eth0/ipv4 << "EOF"
ONBOOT=yes
SERVICE=ipv4-static
IP=192.168.1.1
GATEWAY=192.168.1.2
PREFIX=24
BROADCAST=192.168.1.255
EOF

notice in your static config you have the gateway, you also need that for dhcp to work. your NIC has no clue were to pull its IP from if you do not provide it with a gateway.

dwhitney67 · 11-02-2007, 04:17 PM

lleb -

Are you sure about needing to specify a Gateway? That seems unusual because that is information that I would normally not be required to supply when I connect via DHCP. That information is obtained from the lease-holder (i.e. the router) and it is supposed to be inserted into /etc/resolv.conf by dhclient.

My issue is that dhclient can't talk/communicate with the router to get such information. It almost appears that a port (68) is being blocked.

Btw, from the dhclient man-page:
The DHCP client normally transmits any protocol messages it sends before acquiring
an IP address to, 255.255.255.255, the IP limited broadcast address.