NetworkManager does not manage device after install on IPv6 network

[Loren M. Lang]

When installing Ubuntu Desktop 12.04 with debian-installer on a network with IPv6 enabled, NetworkManager disabled network interfaces from automatically configuring via DHCP in /etc/network/interfaces, but does not disable them from automatically configuring IPv6. This prevents NetworkManager from taking over control and managing the network interface because it still appears to be maintained by the ifupdown, but has IPv4 disabled from configuring at all. The resultant /etc/network/interfaces file looks like this:

# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).

# The loopback network interface
auto lo
iface lo inet loopback

# The primary network interface
auto eth0
#NetworkManager#iface eth0 inet dhcp
# This is an autoconfigured IPv6 interface
iface eth0 inet6 auto

Because there is a non-commented iface line for eth0, NetworkManager never takes over management. My system is:
Description: Ubuntu 12.04 LTS
Release: 12.04
network-manager 0.9.4.0-0ubuntu4

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Loren M. Lang (penguin359)]

I encountered this bug while using debian-installer to install Ubuntu Desktop on an IPv6 network. If using preseeding to automate an install of Ubuntu Desktop, the following command can be added to preseed/late_command as a quick workaround:

in-target sed -i '/^iface eth0 /s/^/#NetworkManager#/' /etc/network/interfaces

[Mathieu Trudel-Lapierre (cyphermox)]

Can you please also provide an example for a file that doesn't properly get modified?

I've been testing this, but on my system the /etc/network/interfaces file gets properly commented for inet6 entries as well, even without your changes. My tests were done with the following settings:

auto eth0
iface eth0 inet dhcp
iface eth0 inet6 dhcp auto

Granted, there were no additional settigns for the inet6 stanza.

[Mathieu Trudel-Lapierre (cyphermox)]

I fail at reading... definitely, this bug is destined to have issues with me ;)

[Mathieu Trudel-Lapierre (cyphermox)]

I ended up revising it pretty heavily; but about to merge and upload to my PPA for testing (until Quantal Alpha-1 is released)

[Loren M. Lang (penguin359)]

Here a snippet from the file that gets generated by debian-installer (or one of it's packages) before NM has it's hands on it. It will fail to be modified correctly prior to my change:

# The primary network interface
auto eth0
iface eth0 inet dhcp
# This is an autoconfigured IPv6 interface
iface eth0 inet6 auto

The stock ifblacklist_migrate.sh script creates this:

# The primary network interface
auto eth0
#NetworkManager#iface eth0 inet dhcp
# This is an autoconfigured IPv6 interface
iface eth0 inet6 auto

My modified version will change the original file to this:

# The primary network interface
auto eth0
#NetworkManager#iface eth0 inet dhcp
# This is an autoconfigured IPv6 interface
#NetworkManager#iface eth0 inet6 auto

[Launchpad Janitor (janitor)]

This bug was fixed in the package network-manager - 0.9.4.0+git201206081144.2efeac8-0ubuntu1

---------------
network-manager (0.9.4.0+git201206081144.2efeac8-0ubuntu1) quantal; urgency=low

  [ Mathieu Trudel-Lapierre ]
  * upstream snapshot 2012-06-08 11:44:43 (GMT)
    + 2efeac8c5f84d55db2779eb27e29eb4c40132540
  * debian/control: add dbus to Build-Depends.
  * debian/control: add libsoup2.4-dev (>= 2.26) to Build-Depends for
    connectivity checking support.
  * debian/patches/70_lp145653_no_sigaction_for_crashes.patch: refreshed.
  * debian/patches/git_*.patch: dropped, included upstream.
  * debian/patches/lp949743_ensure_remoteconnection_disconnects_494f0a2.patch:
    dropped, included upstream.
  * debian/patches/fix-test18.patch: dropped, included upstream.
  * debian/patches/ipw2x00-no-nl80211.patch: dropped, included upstream.
  * debian/patches/lp990011_use_tempaddr_sysctl_default.patch: update to also
    check /etc/sysctl.d/10-ipv6-privacy.conf.
  * debian/libnm-glib4.symbols: add more symbols:
    + nm_object_error_get_type@Base
    + nm_object_error_quark@Base
    + nm_device_adsl_error_get_type@Base
    + nm_device_adsl_error_quark@Base
    + nm_device_adsl_get_carrier@Base
    + nm_device_adsl_get_type@Base
    + nm_device_adsl_new@Base
    + nm_device_get_autoconnect@Base
    + nm_device_set_autoconnect@Base
    + nm_device_get_driver_version@Base
    + nm_device_get_firmware_version@Base
  * debian/libnm-util2.symbols: add symbols:
    + nm_setting_wireless_get_hidden@Base
    + nm_connection_get_setting_adsl@Base
    + nm_setting_adsl_error_get_type@Base
    + nm_setting_adsl_error_quark@Base
    + nm_setting_adsl_get_*@Base
    + nm_setting_adsl_new@Base
  * debian/ifblacklist_migrate.sh:
    - also comment out the "auto $iface" line for an interface stanza.
    - match "inet6 auto" as well when looking for interfaces to comment out.
  * debian/debug-helper.py: fix permissions.

  [ Loren M. Lang ]
  * debian/ifblacklist_migrate.sh:
    - match and comment out inet6 "auto" interface stanzas. (LP: #1005091)
 -- Mathieu Trudel-Lapierre <email address hidden> Fri, 08 Jun 2012 13:35:07 -0400