dhclient on Debian Jessie not sending the same identifier for DHCPv4 and DHCPv6 (RFC 4361)
dhcp at nryc.fr
Tue Sep 8 14:55:15 UTC 2015
I'm currently testing RFC 4361 (CHCPv4 + DHCPv6 + DDNS), with :
- a dual-stack DNS server,
- an IPv4-only DHCPv4 server,
- an IPv6-only DHCPv6 server,
- a dual-stack client.
All of those are Debian Jessie 64-bits machines. DHCP servers are
configured with "ddns-update-style standard".
The client is configured with :
iface eth0 inet dhcp
iface eth0 inet6 dhcp
And "send fqdn.fqdn = gethostname();" in /etc/dhcp/dhclient.conf
(instead of "send host-name").
The client receives its IPv4/v6 addresses correctly but its not
submitting the same identifier to the DHCP resulting a conflict during DDNS.
I tried using the "-I -D LLT" parameters with dhclient which is supposed
to make the DHCPv4 client use the same DUID as the DHCPv6 client :
But it doesn't work, the DHCID in the DNS is not the same.
This is the result in the forward zone (rfc4361.test) when I use
"dhclient -4 -I -D LLT eth0" :
dual-test.rfc4361.test. 300 IN DHCID
dual-test.rfc4361.test. 300 IN A 172.20.56.100
This is the result in the forward zone when I use "dhclient -6 -I -D LLT
dual-test.rfc4361.test. 187 IN DHCID
dual-test.rfc4361.test. 187 IN AAAA 2001:660:3305:122::f5c
Thanks for your help,
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