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NetworkManager supports the IPv6 protocol and it is turned on by default, but its IPv6 configuration implementation is far from perfect. Right now (May 2012) we are trying to fix NetworkManager so that it is capable of starting an IPv6-only connection in all common situations. This doesn't mean that NetworkManager will be RFC compliant in near future.
NetworkManager supports the IPv6 protocol and it is turned on by default. It connects to networks with SLAAC and DHCPv6 and keeps the connection running. Many bugs have been fixed recently, so it's possible that it doesn't
Please note that full IPv6 configuration support is a bit more complicated than IPv4.  
work well in your distribution. Reasonably good support will be delivered with NetworkManager 9.6 and Linux 3.5.  


Due to the existence of IPv6 link-local addresses, routing configuration and address configuration are orthogonal.
Due to the existence of IPv6 link-local addresses, routing configuration and address configuration are orthogonal.


IPv6 ''is'' different.
Please remember that IPv6 ''is'' different.


== Static configuration ==
For details about possible IPv6 scenarios, see [[Networking/Addressing#Dynamic_IPv6_configuration]].


No RA or DHCP configuration. NetworkManager supports static configuration out of the box.
== IPv6 Privacy Extensions ==


The only caveat is that the configuration assumes that default gateways belong to addresses. This is not true
NetworkManager supports [http://tools.ietf.org/html/rfc4941 privacy extensions] through the 'ip6-privacy' key.
with IPv6. Strictly speaking, this is not even true with IPv4, but the dependency between configured IPv4 addresses and gateways is much stronger.


== Automatic configuration ==
An example of a minimally configured keyfile (placed in /etc/NetworkManager/system-connections) is below. Values for the connection section may be obtained using the <code>nmcli connection</code> command.
<pre>[connection]
id=
uuid=
type=


To experiment with automatic IPv6 configuration in NetworkManager we recommend trying one or more of
[ipv6]
the following scenarios:
method=auto
ip6-privacy=2</pre>


=== SLAAC without DNS configuration (mandatory by [http://tools.ietf.org/html/rfc4294 RFC 4294]) ===
Or edit a gui created config file at /etc/sysconfig/network-scripts/ifcfg-* and add
IPV6_PRIVACY=rfc3041


/etc/radvd.conf:
== Debugging ==
 
You can run NetworkManager on foreground with various debugging settings:


<pre>
<pre>
interface eth0 {
/path/to/NetworkManager --no-daemon \
    AdvSendAdvert on;
     --log-level=debug --log-domains=DEVICE,IP6,DHCP6 2>~/nm.debug
     prefix 2001:db8:1:2::/64 {};
};
</pre>
</pre>


DNS queries typically use IPv4. NetworkManager
Be careful not to run multiple instances of NetworkManager. Check with <code>ps -ef</code> if you experience weird behavior.
supports this configuration and it also works
 
when device is ignored by NetworkManager.
== Long-term goals ==


=== SLAAC with RDNSS and DNSSL ===
* Don't tear down interfaces, keep link-local networking always on
* Get kernel problems fixed, then simplify ipv6 handling in NM


/etc/radvd.conf:
== Recently fixed ==


<pre>
=== Git ===
interface eth0 {
 
    AdvSendAdvert on;
[https://bugzilla.gnome.org/show_bug.cgi?id=676317 Gnome Bug 676317 - IPv6 DHCPv6 configuration fails: nm_system_replace_default_ip6_route returns -7]
    prefix 2001:db8:1:2::/64 {};
    RDNSS 2001:db8:1:2::ab {};
    DNSSL example.net {};
};
</pre>


The contents of host's /etc/resolv.conf is filled in by NetworkManager. Linux kernel
[https://bugzilla.gnome.org/show_bug.cgi?id=676740 Gnome Bug 676740 - NetworkManager fails to configure DHCPv6 address under some circumstances (because it 'assumes')]
currently supports RDNSS but not DNSSL. NetworkManager has problems with RDNSS but they
have to be solved also on IETF level. DNSSL support cannot be tested in NetworkManager because
of lack of kernel support. Kernel 3.5 will have DNSSL support.


[https://bugzilla.gnome.org/show_bug.cgi?id=676322 Gnome Bug 676322 - IPv6 DNSSL does not get into /etc/resolv.conf]
[https://bugzilla.gnome.org/show_bug.cgi?id=676322 Gnome Bug 676322 - IPv6 DNSSL does not get into /etc/resolv.conf]
Line 56: Line 54:


[https://bugzilla.redhat.com/show_bug.cgi?id=753482 Fedora Bug 753482 - wifi drops every 15 minutes (ip-config-unavailable) because of IPv6 RDNSS timeout]
[https://bugzilla.redhat.com/show_bug.cgi?id=753482 Fedora Bug 753482 - wifi drops every 15 minutes (ip-config-unavailable) because of IPv6 RDNSS timeout]
[https://bugs.launchpad.net/ubuntu/+source/network-manager/+bug/936714 Ubuntu Bug 936714 - IPv6 DNS search list (DNSSL) isn't passed to userspace by the kernel]


[http://www.ietf.org/mail-archive/web/ipv6/current/msg15816.html IETF IPv6 Mailing List – question on RDNSS, RFC 6106 part 5.1]
[http://www.ietf.org/mail-archive/web/ipv6/current/msg15816.html IETF IPv6 Mailing List – question on RDNSS, RFC 6106 part 5.1]


=== SLAAC with DHCPv6 Information Request ===
== WONTFIX / NOTABUG ==
 
/etc/radvd.conf:
 
<pre>
interface eth0 {
    AdvSendAdvert on;
    AdvOtherConfigFlag on;
    prefix 2001:db8:1:2::/64 {};
};
</pre>
 
/etc/dhcp/dhcpd6.conf:
 
<pre>
subnet6 2001:db8:1:2::/64 {
    option dhcp6.name-servers 2001:db8:1:2::ab;
    option dhcp6.domain-search "example.net";
}
</pre>
 
This is often used to supply DNS information to hosts that don't support
RDNSS/DNSSL in Router Advertisements. NetworkManager works well in this
scenario if DHCPv6 packets get through firewall.
 
There have been problems with IPv6 firewall blocking DHCPv6 exchange. Right
now Fedora has two firewall configuration services. I hope to test both of them later.
 
=== DHCPv6 address-only, all other by RA ===
 
/etc/radvd.conf:
 
<pre>
interface eth0 {
    AdvSendAdvert on;
    AdvManagedFlag on;
    prefix 2001:db8:1:2::/64 {
        AdvAutonomous off;
    };
    RDNSS 2001:abcd:1:1::ab {};
    DNSSL example.net {};
};
</pre>
 
/etc/dhcp/dhcpd6.conf:
 
<pre>
subnet6 2001:db8:1:2::/64 {
    range6 2001:db8:1:2::1:0000 2001:db8:1:2::1:ffff;
}
</pre>
 
DHCPv6 is used only for address configuration, RA does everything else. NetworkManager
works in this scenario except DNSSL (see above).
 
=== DHCPv6 address and DNS configuration ===
 
/etc/radvd.conf:
 
<pre>
interface eth0 {
    AdvSendAdvert on;
    AdvManagedFlag on;
    AdvOtherConfigFlag on;
    prefix 2001:db8:1:2::/64 {
        AdvAutonomous off;
    };
};
</pre>
 
/etc/dhcp/dhcpd6.conf:
 
<pre>
subnet6 2001:db8:1:2::/64 {
    option dhcp6.name-servers 2001:db8:1:2::ab;
    option dhcp6.domain-search "example.net";
    range6 2001:db8:1:2::1:0000 2001:db8:1:2::1:ffff;
}
</pre>
 
This is a typical DHCPv6 configuration. Note that routing information are stil delivered
through Router Advertisements. NetworkManager may fail in this scenario.
 
[https://bugzilla.gnome.org/show_bug.cgi?id=676317 Gnome Bug 676317 - IPv6 DHCPv6 configuration fails: nm_system_replace_default_ip6_route returns -7]
 
[https://bugzilla.gnome.org/show_bug.cgi?id=676740 Gnome Bug 676740 - NetworkManager fails to configure DHCPv6 address under some circumstances (because it 'assumes')]
 
=== Atypical configurations ===


[https://bugzilla.gnome.org/show_bug.cgi?id=677099 Gnome Bug 677099 - IPv6: NetworkManager configures RDNSS and DNSSL though DHCPv6 even though AdvOtherConfigFlag is not set]
[https://bugzilla.gnome.org/show_bug.cgi?id=677099 Gnome Bug 677099 - IPv6: NetworkManager configures RDNSS and DNSSL though DHCPv6 even though AdvOtherConfigFlag is not set]
== Debugging ==
You can run NetworkManager on foreground with various debugging settings:
<pre>
/path/to/NetworkManager --no-daemon \
    --log-level=debug --log-domains=DEVICE,IP6,DHCP6 2>~/nm.debug
</pre>
Be careful not to run multiple instances of NetworkManager. Check with <code>ps -ef</code> if you experience weird behavior.

Latest revision as of 22:03, 8 September 2013

NetworkManager supports the IPv6 protocol and it is turned on by default. It connects to networks with SLAAC and DHCPv6 and keeps the connection running. Many bugs have been fixed recently, so it's possible that it doesn't work well in your distribution. Reasonably good support will be delivered with NetworkManager 9.6 and Linux 3.5.

Due to the existence of IPv6 link-local addresses, routing configuration and address configuration are orthogonal.

Please remember that IPv6 is different.

For details about possible IPv6 scenarios, see Networking/Addressing#Dynamic_IPv6_configuration.

IPv6 Privacy Extensions

NetworkManager supports privacy extensions through the 'ip6-privacy' key.

An example of a minimally configured keyfile (placed in /etc/NetworkManager/system-connections) is below. Values for the connection section may be obtained using the nmcli connection command.

[connection]
id=
uuid=
type=

[ipv6]
method=auto
ip6-privacy=2

Or edit a gui created config file at /etc/sysconfig/network-scripts/ifcfg-* and add

IPV6_PRIVACY=rfc3041

Debugging

You can run NetworkManager on foreground with various debugging settings:

/path/to/NetworkManager --no-daemon \
    --log-level=debug --log-domains=DEVICE,IP6,DHCP6 2>~/nm.debug

Be careful not to run multiple instances of NetworkManager. Check with ps -ef if you experience weird behavior.

Long-term goals

  • Don't tear down interfaces, keep link-local networking always on
  • Get kernel problems fixed, then simplify ipv6 handling in NM

Recently fixed

Git

Gnome Bug 676317 - IPv6 DHCPv6 configuration fails: nm_system_replace_default_ip6_route returns -7

Gnome Bug 676740 - NetworkManager fails to configure DHCPv6 address under some circumstances (because it 'assumes')

Gnome Bug 676322 - IPv6 DNSSL does not get into /etc/resolv.conf

Fedora Bug 824121 - IPv6: Kernel doesn't propagate DNSSL to userspace (e.g. NetworkManager)

Fedora Bug 753482 - wifi drops every 15 minutes (ip-config-unavailable) because of IPv6 RDNSS timeout

IETF IPv6 Mailing List – question on RDNSS, RFC 6106 part 5.1

WONTFIX / NOTABUG

Gnome Bug 677099 - IPv6: NetworkManager configures RDNSS and DNSSL though DHCPv6 even though AdvOtherConfigFlag is not set