In the following part of syslog it appears, though, that NM is managing eth0 after saying that it's "now unmanaged"!
May 8 18:36:49 k8u NetworkManager: <info> (eth0): now unmanaged [...] May 8 18:36:51 k8u dhclient: There is already a pid file /var/run/dhclient.eth0.pid with pid 3094 May 8 18:36:51 k8u dhclient: killed old client process, removed PID file May 8 18:36:51 k8u dhclient: Internet Systems Consortium DHCP Client V3.1.1 May 8 18:36:51 k8u dhclient: Copyright 2004-2008 Internet Systems Consortium. May 8 18:36:51 k8u dhclient: All rights reserved. May 8 18:36:51 k8u dhclient: For info, please visit http://www.isc.org/sw/dhcp/ May 8 18:36:51 k8u dhclient: May 8 18:36:51 k8u dhclient: wmaster0: unknown hardware address type 801 May 8 18:36:51 k8u dhclient: parse_option_param: Bad format a May 8 18:36:51 k8u dhclient: wmaster0: unknown hardware address type 801 May 8 18:36:51 k8u dhclient: Listening on LPF/eth0/00:0d:61:ed:05:82 May 8 18:36:51 k8u dhclient: Sending on LPF/eth0/00:0d:61:ed:05:82 May 8 18:36:51 k8u dhclient: Sending on Socket/fallback May 8 18:36:51 k8u dhclient: DHCPRELEASE on eth0 to 192.168.1.254 port 67 May 8 18:36:51 k8u NetworkManager: <info> (eth0): carrier now OFF (device state 1) May 8 18:36:51 k8u dhclient: Internet Systems Consortium DHCP Client V3.1.1 May 8 18:36:51 k8u dhclient: Copyright 2004-2008 Internet Systems Consortium. May 8 18:36:51 k8u dhclient: All rights reserved. May 8 18:36:51 k8u dhclient: For info, please visit http://www.isc.org/sw/dhcp/ May 8 18:36:51 k8u dhclient: May 8 18:36:51 k8u dhclient: wmaster0: unknown hardware address type 801 May 8 18:36:51 k8u NetworkManager: <info> (eth0): carrier now ON (device state 1) -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to network-manager in Ubuntu. https://bugs.launchpad.net/bugs/374006 Title: dhcp fails, but succeeds after ifdown/ifup in rc.local Status in “network-manager” package in Ubuntu: New Bug description: Binary package hint: network-manager The bug occurred after upgrading to jaunty. I'm not sure about the network-manager, it could also be the kernel, a driver for my network card, or perhaps the cause in the reorderings done to increase the booting speed in jaunty. Also I expect this to be duplicate bug, but I couldn't determine an existing one that was really close enough. I reported this earlier at this existing report, but then found that ubuntu-bug is preferred, so I'm repeating this here: can't connect via dhcp https://bugs.launchpad.net/bugs/312157 After boot using the default kernel there is no wired connection to the internet, but everything on the local network is available. (ping by name to local machines works, but pop for email fails.) If I did not have another machine on the local network, I would have had no way to know how to fix this, as this isolates the upgraded machine from the internet. I can always correct this by doing: sudo ifdown eth0 sudo ifup eth0 Since this is repeatable, I'd like to hunt it down to the source of the problem, but I have no idea how to proceed. The network icon in the system tray does not show an active network (neither wired nor wireless) before and after the ifdown/ifup fix. Any suggestions as to what I could do to fix this? ProblemType: Bug Architecture: i386 DistroRelease: Ubuntu 9.04 Gconf: Package: network-manager 0.7.1~rc4.1.cf199a964-0ubuntu2 ProcEnviron: PATH=(custom, user) LANG=nl_NL.UTF-8 SHELL=/bin/bash SourcePackage: network-manager Uname: Linux 2.6.28-11-generic i686 WpaSupplicantLog: To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/network-manager/+bug/374006/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp