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No DHCPOFFERS received

I am trying to get connectded to my ISP via DHCP, from a IBM Thinkpad R60, Dual Core (intel processor, 1.66 GHz). I have successfully installed FC6, but the ethernet card (Broadcom Corporation NetXtreme BCM5751M Gigabit Ethrnet PCI Express) seem not to be recognised.
I am using the default driver (tg3) from FC6, and the Ethernet Card seems to be working ("ping localhost" responds positively).

Note that using my previous laptop (TP R50e, with a different card) I never experienced any problem -> I can not believe that the problem is with my ISP...

For more information, here is the output from ifconfig:

[root@cosmo-lap2 ~]# ifconfig
eth0 Link encap:Ethernet HWaddr 00:16: D3:29:3E:4A
inet6 addr: fe80::216:d3ff:fe29:3e4a/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:8 errors:0 dropped:0 overruns:0 frame:0
TX packets:22 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:2788 (2.7 KiB) TX bytes:5508 (5.3 KiB)
Interrupt:201

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:1866 errors:0 dropped:0 overruns:0 frame:0
TX packets:1866 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:4817052 (4.5 MiB) TX bytes:4817052 (4.5 MiB)
====================

and here is the /var/log/messages for one typical session:
Dec 3 09:42:59 cosmo-lap2 gconfd (root-2987): starting (version 2.14.0), pid 2987 user 'root'
Dec 3 09:42:59 cosmo-lap2 gconfd (root-2987): Resolved address "xml:readonly:/etc/gconf/gconf.xml.mandatory" to a read-only configuration source at position 0
Dec 3 09:42:59 cosmo-lap2 gconfd (root-2987): Resolved address "xml:readwrite:/root/.gconf" to a writable configuration source at position 1
Dec 3 09:42:59 cosmo-lap2 gconfd (root-2987): Resolved address "xml:readonly:/etc/gconf/gconf.xml.defaults" to a read-only configuration source at position 2
Dec 3 09:43:11 cosmo-lap2 kernel: ADDRCONF(NETDEV_UP): eth0: link is not ready
Dec 3 09:43:13 cosmo-lap2 kernel: tg3: eth0: Link is up at 100 Mbps, full duplex.
Dec 3 09:43:13 cosmo-lap2 kernel: tg3: eth0: Flow control is on for TX and on for RX.
Dec 3 09:43:13 cosmo-lap2 kernel: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
Dec 3 09:43:13 cosmo-lap2 kernel: audit(1165138993.344:18): avc: denied { write } for pid=3108 comm="ifconfig" name="[13133]" dev=pipefs ino=13133 scontext=system_u:system_r:ifconfig_t:s0 tcontext=system_u:system_r:unconfined_t:s0 tclass=fifo_file
Dec 3 09:43:13 cosmo-lap2 kernel: audit(1165138993.344:19): avc: denied { write } for pid=3108 comm="ifconfig" name="[13133]" dev=pipefs ino=13133 scontext=system_u:system_r:ifconfig_t:s0 tcontext=system_u:system_r:unconfined_t:s0 tclass=fifo_file
Dec 3 09:43:13 cosmo-lap2 kernel: audit(1165138993.344:20): avc: denied { read } for pid=3108 comm="ifconfig" name="[13084]" dev=pipefs ino=13084 scontext=system_u:system_r:ifconfig_t:s0 tcontext=system_u:system_r:unconfined_t:s0 tclass=fifo_file
Dec 3 09:43:13 cosmo-lap2 kernel: audit(1165138993.344:21): avc: denied { write } for pid=3108 comm="ifconfig" name="[13084]" dev=pipefs ino=13084 scontext=system_u:system_r:ifconfig_t:s0 tcontext=system_u:system_r:unconfined_t:s0 tclass=fifo_file
Dec 3 09:43:13 cosmo-lap2 kernel: audit(1165138993.344:22): avc: denied { read } for pid=3108 comm="ifconfig" name="[13085]" dev=pipefs ino=13085 scontext=system_u:system_r:ifconfig_t:s0 tcontext=system_u:system_r:unconfined_t:s0 tclass=fifo_file
Dec 3 09:43:13 cosmo-lap2 kernel: audit(1165138993.344:23): avc: denied { write } for pid=3108 comm="ifconfig" name="[13085]" dev=pipefs ino=13085 scontext=system_u:system_r:ifconfig_t:s0 tcontext=system_u:system_r:unconfined_t:s0 tclass=fifo_file
Dec 3 09:43:13 cosmo-lap2 kernel: audit(1165138993.344:24): avc: denied { read } for pid=3108 comm="ifconfig" name="[13086]" dev=pipefs ino=13086 scontext=system_u:system_r:ifconfig_t:s0 tcontext=system_u:system_r:unconfined_t:s0 tclass=fifo_file
Dec 3 09:43:13 cosmo-lap2 kernel: audit(1165138993.344:25): avc: denied { write } for pid=3108 comm="ifconfig" name="[13086]" dev=pipefs ino=13086 scontext=system_u:system_r:ifconfig_t:s0 tcontext=system_u:system_r:unconfined_t:s0 tclass=fifo_file
Dec 3 09:43:13 cosmo-lap2 dhclient: DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 5
Dec 3 09:43:14 cosmo-lap2 avahi-daemon[2409]: New relevant interface eth0.IPv6 for mDNS.
Dec 3 09:43:14 cosmo-lap2 avahi-daemon[2409]: Joining mDNS multicast group on interface eth0.IPv6 with address fe80::216:d3ff:fe29:3e4a.
Dec 3 09:43:14 cosmo-lap2 avahi-daemon[2409]: Registering new address record for fe80::216:d3ff:fe29:3e4a on eth0.
Dec 3 09:43:18 cosmo-lap2 dhclient: DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 9
Dec 3 09:43:27 cosmo-lap2 dhclient: DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 15
Dec 3 09:43:42 cosmo-lap2 dhclient: DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 14
Dec 3 09:43:56 cosmo-lap2 dhclient: DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 12
Dec 3 09:44:08 cosmo-lap2 dhclient: DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 6
Dec 3 09:44:14 cosmo-lap2 dhclient: No DHCPOFFERS received.

=========================================
:confused:
I have already tried to add "irqpoll" and !acpi=off" in the grub loader without success.

Many thanks in advance for any help

why do you thinks that acpi or irq's have anything at all to do with your problem? you have an eth0, so hardware seems fine... you simply seem to be getting no DHCP offers, and you've not mentioned a single thing about your DHCP server... does it exist?

Hi antonucc,

It's probable that your ISP has registered the MAC address of your previous laptop and does not recognize the new machine, denying an IP address to it.

This is a way ISP providers prevent the use of its network by anyone who can plug a computer onto it. You should contact it and explain your change to validate your new computer.

Now: dhpcd not starting and/or running

Quote:

Originally Posted by acid_kewpie

Quote:

Originally Posted by osvaldomarques

It's probable that your ISP has registered the MAC address of your previous laptop and does not recognize the new machine, denying an IP address to

Thanks to both of you: I think you are BOTH right.
First, I have checked my installation and it was true: the dhcp package was actually not installed. But I have also checked about other people's expereicnes with having dhcp from linux running with the modem provieded by my ISP, and it is true that it records the MAC number....Now, I am a :newbie: to these issues, so please, be patient...

I have now reinstalled FC6, and I have included dhcp and dhcpv6 among the customised packages chosen for installation. However, I have chosen not to get the ISP number directly from my ISP at the installation, because of the above mentioned "locking" of the modem on the MAC number of the old laptop.

Now, at the end dhcp and dhcpv6 seem to be installed, but when I try to run dhpcd it fails, because it seems to look for the IP number of the eth0 interface, and (of course) does not find any. Note: I have copied the dhcpd.conf file in /etc, and added the "authoritative;" command. I also try to launch it manually after having restarted the netwrok services - it fails for the same reason.

Clearly, I have done some mistakes in dhpcd.conf.
Does anybody have a good pointer to a howto/guide on how to configure a dhcp client? :study:

Once again, many thanks in advance

dhcp clients do not require configuration by default. you can fine tune them, but it's really very rare to need to touch the config at all. if, as suggested above, it's the ISP who's serving DHCP then a call to their helpdesk would probably be the key. if it's actually DHCP being served locally, e.g. from a simple ADSL router, then it'd be the configuration on that router.

Hi antonucc,

The dhcpd package, including the dhcpd.conf are a server package, for you offer leases to your possible other machines, on a configured ethernet. When you try to get an address lease, it's the dhcpcd package which is used.

If you want to access internet via your new machine, you need to contact your ISP provider to change the MAC. There

you wont need dhcpv6 for a while unless you just want to play with IPv6.

If you plug in a device to the modem, and then try another, you need to reboot your cable modem before it will pass traffic with the new MAC address.

Installing a DHCP server on the laptop is not the answer.

Quote:

Originally Posted by osvaldomarques

Thanks to all for your comments/suggestions/answers. It turned out that, after having correctly installed dhcp, the final problem I had was the one which osvaldomarques noticed: the modem was locked on the old laptop's MAC number. I called the support service of my ISP and got it unlocked: now it works. :)

:study: Looking back at this experience, I think that I could not understand the difference between server and client dhcp. I only needed to have a client dhcp to be working, just to get connected to a modem, not a server. So, the dhcpd.conf file was not an issue. Now, I could not find among the various Howtos' a clear explanation of what-is-needed-for-what. The only DHCP Howto I found goes back to 2002. What would be eneeded is a "quick start" section, where it is writte: "do this and this if you just want to be connected"....

Thanks again to all of you