eth0 does not get an IP-address from DHCP anymore

[Danny Colligan]

Have you checked the other interfaces?  Something that Ubuntu is
notorious for doing on upgrades is switching the interfaces around...
perhaps eth0 is not what you think it is anymore.

Danny Colligan

> I installed Ubuntu Feisty (AMD64) using this manual, exept for the
> last step (install the ubuntu-desktop):
> https://help.ubuntu.com/7.04/installation-guide/amd64/linux-upgrade.html
> A really nice small setup if you want to have a minimal installation
> and a good start for custom installs.
>
> After my installation everything was working as expected but suddenly
> after a reboot my network didn't receive DHCP-leases anymore. I'm
> stuck and need help to solve this problem.
>
> I have searched the net for different solutions but haven't found any
> that matches my problem.
>
> The obvious question is "What did you do before the reboot?", as those
> things might have messed things up.
> I only updated the installation with "# aptitude update && aptitude
> upgrade" and installed a fiew packages using "# aptitude install acpid
> cpufreqd sensors"
>
> If I boot the computer from the live-CD I get an IP-number from my
> DHCP-server, so there should be support for the hardware. And I had
> the network up and running during the upgrade and the installation,
> and the network (outside my computer, DHCP-server, switch, cables etc)
> are fully functional.
>
> Here are a fiew commands I have tried (in chronological order).
> If you need more information about my system, or have ideas on how to
> slove it, please tell me.
> I think it might have something to do with the "Permission denied"
> output, but I can't figure out what.
>
> // Start Of Testing
> # ps -aux | grep dhcp
> dhcp      4632  0.0  0.1  14092   736 ?        S<s  23:09   0:00
> dhclient3 -pf /var/run/dhclient.eth0.pid -lf
> /var/lib/dhcp3/dhclient.eth0.leases eth0
> root      4669  0.0  0.1   3860   584 tty1     S+   23:15   0:00 grep dhcp
>
> # ifconfig eth0
> eth0      Link encap:Ethernet  HWaddr 00:16:E7:56:C1:0E
>           BROADCAST MULTICAST  MTU:1500  Metric:1
>           RX packets:0 errors:0 dropped:0 overruns:0 frame:0
>           TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
>           collisions:0 txqueuelen:1000
>           RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)
>           Interrupt:23 Base address:0x4000
>
> # /etc/init.d/networking restart
> There is already a pid file /var/run/dhclient.eth0.pid with pid 6847440
> Internet Systems Consortium DHCP Client V3.0.4
> Copyright 2004-2006 Internet Systems Consortium.
> All rights reserved.
> For info, please visit http://www.isc.org/sw/dhcp/
>
> SIOCSIFADDR: Permission denied
> SIOCSIFFLAGS: Permission denied
> SIOCSIFFLAGS: Permission denied
> Listening on LPF/eth0/00:16:e7:56:c1:0e
> Sending on   LPF/eth0/00:16:e7:56:c1:0e
> Sending on   Socket/fallback
> receive_packet failed on eth0: Network is down
> DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 5
> send_packet: Network is down
> DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 6
> send_packet: Network is down
> DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 10
> send_packet: Network is down
> DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 10
> send_packet: Network is down
> No DHCPOFFERS received.
> No working leases in persistent database - sleeping.
>
> # ifdown eth0
> There is already a pid file /var/run/dhclient.eth0.pid with pid 5072
> killed old client process, removed PID file
> Internet Systems Consortium DHCP Client V3.0.4
> Copyright 2004-2006 Internet Systems Consortium.
> All rights reserved.
> For info, please visit http://www.isc.org/sw/dhcp/
>
> Listening on LPF/eth0/00:16:e7:56:c1:0e
> Sending on   LPF/eth0/00:16:e7:56:c1:0e
> Sending on   Socket/fallback
>
> # ifconfig eth0 up
> (no output)
>
> # ifup eth0
> There is already a pid file /var/run/dhclient.eth0.pid with pid 6847440
> Internet Systems Consortium DHCP Client V3.0.4
> Copyright 2004-2006 Internet Systems Consortium.
> All rights reserved.
> For info, please visit http://www.isc.org/sw/dhcp/
>
> SIOCSIFADDR: Permission denied
> SIOCSIFFLAGS: Permission denied
> SIOCSIFFLAGS: Permission denied
> Listening on LPF/eth0/00:16:e7:56:c1:0e
> Sending on   LPF/eth0/00:16:e7:56:c1:0e
> Sending on   Socket/fallback
> DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 8
> DHCPOFFER from 172.16.2.1
> DHCPREQUEST on eth0 to 255.255.255.255 port 67
> DHCPACK from 172.16.2.1
> SIOCSIFADDR: Permission denied
> SIOCSIFFLAGS: Permission denied
> SIOCSIFNETMASK: Permission denied
> SIOCSIFBRDADDR: Permission denied
> SIOCSIFFLAGS: Permission denied
> SIOCADDRT: Operation not permitted
> [CTRL + C] (process never exit, so I terminated it after 5 minutes)
>
> # ifconfig eth0
> eth0      Link encap:Ethernet  HWaddr 00:16:E7:56:C1:0E
>           inet6 addr: fe80::216:e7ff:fe56:c10e/64 Scope:Link
>           UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
>           RX packets:17 errors:0 dropped:0 overruns:0 frame:0
>           TX packets:8 errors:0 dropped:0 overruns:0 carrier:0
>           collisions:0 txqueuelen:1000
>           RX bytes:1963 (1.9 KiB)  TX bytes:1152 (1.1 KiB)
>           Interrupt:23 Base address:0x4000
>
> // End Of Testing
>
> Thanks,
> Anders
>