[systemd-devel] systemd-networkd not sending DHCP v6 requests

[Ian Pilcher]

On 07/11/2017 02:58 AM, Lennart Poettering wrote:
> Note that DHCPv6 is not done unless IPv6 RA packets tell networkd to
> do so. Hence, areyou sure the RA spoken on your network properly
> indicates that?

Interesting.  I am seeing somewhat different behavior (but note that
this is systemd-networkd 219 on CentOS 7, which is pretty old).

* On networks with no router advertisements at all, systemd-networkd 219
   will eventually send out dhcp6 solicit packets.

* On a network with router advertisements that include prefix info
   (option 3), systemd-networkd 219 will send dhcp6 solicit packets.

* If the router advertisements on a network do not include any prefix
   information, however, systemd-networkd 219 will never send any dhcp6
   solicit packets and never configure an IPv6 address.

Unfortunately, my ISP's router sends RAs without prefix information.
(Clients get their addresses via DHCPv6, and are presumably expected to
simply assume a 64 bit prefix length.)

So it looks like I won't be able to use systemd-networkd to get around
the dhclient wall clock problem, at least until RHEL/CentOS see an
updated version of systemd (systemd-networkd 231 does seem to behave
differently).

-- 
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Ian Pilcher                                         arequipeno at gmail.com
-------- "I grew up before Mark Zuckerberg invented friendship" --------
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