ipv6 dhcp client never started.

[kenjo]

I'm in a ipv6 network that sets ip number with dhcpv6 and not using the stateless protocol.

but using ubuntu 15.04 there is never any dhclient started for ipv6 and no way to change any configuration that I can find to start it.

if I attach the cable and then manually start dhclient with "dhclient -6 -i eth3_109" I do get a ipv6 address and things works as intended.

There has to be some way to star the dhclient software from network manager but I can't find it.

There should be two dhclients started per network device one for ipv4 and one for ipv6 only one is started for me.

ProblemType: Bug
DistroRelease: Ubuntu 15.04
Package: network-manager 0.9.10.0-4ubuntu15.1
Uname: Linux 4.1.5-040105-generic x86_64
NonfreeKernelModules: wl
ApportVersion: 2.17.2-0ubuntu1.2
Architecture: amd64
CurrentDesktop: Unity
Date: Fri Aug 14 14:32:06 2015
IfupdownConfig:
 # interfaces(5) file used by ifup(8) and ifdown(8)
 auto lo
 iface lo inet loopback
InstallationDate: Installed on 2015-04-09 (126 days ago)
InstallationMedia: Ubuntu 15.04 "Vivid Vervet" - Beta amd64 (20150326)
IpRoute:
 default via 10.10.1.254 dev eth3 proto static metric 1024
 10.10.1.0/24 dev eth3 proto kernel scope link src 10.10.1.156
 10.10.6.0/24 dev eth3_109 proto kernel scope link src 10.10.6.14
 169.254.0.0/16 dev eth3 scope link metric 1000
NetworkManager.state:
 [main]
 NetworkingEnabled=true
 WirelessEnabled=false
 WWANEnabled=true
 WimaxEnabled=true
SourcePackage: network-manager
UpgradeStatus: No upgrade log present (probably fresh install)
nmcli-nm: Error: command ['nmcli', '-f', 'all', 'nm'] failed with exit code 2: Error: Object 'nm' is unknown, try 'nmcli help'.

[Launchpad Janitor (janitor)]

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

[Marcelo Zacarias da Silva (marcelo-ciagri)]

Tried others distros (basead on debian testing) with newer network-manager (1.0.6) and the problem persists.

[Pasi Sjöholm (pasi-sjoholm)]

What I'm experiencing is that.. if I connect another device into a network (one which has a working dhcpv6-client-software) the network-manager-based device will also get IPv6-address but I I don't.. the network-manager based device never gets IPv6-address.

[Ernst Mikkelsen (erpomik)]

I am certain, that this is the problem I have been fighting for days now.
What I see in my network traces is, that Ubuntu (16.04.2) sends out a Solicit XID request with a Client ID DUID Type set to 4 which I believe is for Stateless DHCP. For Stateful DHCP the DUID Type should be set to 1.

[Marcelo Zacarias da Silva (marcelo-ciagri)]

I think the problem is not related to NetworkManager but dhclient itself. Trying to use DHCPv6 in a Debian 8 machine (no GUI/NM) (using "iface eth0 inet6 dhcp" in /etc/network/interfaces) the "dhclient -6" instance is not started either). Only after I run dhclient manually once (as observed by the OP) it starts working. I use:

# dhclient -6 -d eth0

Doing this the DUID (type 1) is generated and the configuration manager works as expected (networkmanager in Ubuntu or ifup/ifdown in Debian).

[Marcelo Zacarias da Silva (marcelo-ciagri)]

After some testing, it seems that the problem is fixed in Debian 9 (stretch/testing). So I believe some future version of Ubuntu based on Debian 9 (17.10?) will have the fix.