Re: dns update for ipv6 using dhcpv6



On Tue, 2016-12-13 at 16:13 +0000, Tim Coote wrote:
Hullo
I’m trying to build a homenet environment that includes some fedora
25 vms running NetworkManager-1.4.2-1.fc25.x86_64.  I’d like these
computers to update dns when they get new ipv6 addresses. Working
from the discussion on this page: http://bit.ly/2hr2SnC, I was able
to construct a suitable dhclient6-eth0.conf to run directly with
dhclient by adding a line:

send fqdn.fqdn “wibble.example.com”

to the file created by NetworkManager in /var/lib/NetworkManager/.
With the extra line, the relevant update is forwarded by dhclient.

However, I cannot work out where or what to put in NetworkManager’s
or the redhat configuration to get NM to create a suitable dhclient6-
eth0.conf file.

I also noted that the issue noted on the link above about ipv6.dhcp-
hostname getting blown away each time the service is reset still
holds with the nm version.

Am I looking at the right area to get the dns updated? If so, where
should I be putting the configuration to get the right autogenerated
dhclient file?

Thanks in advance

Hi Tim,

sidenote:

When you use dhcp plugin "dhclient" (in NetworkManager.conf), then
NetworkManager generates a suitable dhclient configuration in
/var/lib/NetworkManager/dhclient-*.conf

Don't modify that file, because it will be overwritten.


NM merges other sources files into this file, so you can put your
options there:
https://cgit.freedesktop.org/NetworkManager/NetworkManager/tree/src/dhcp/nm-dhcp-dhclient.c?id=eb77d4ed28fb7d72020fc4bce2a7f3477f0b8c1d#n219

If you turn on debug-logging, NM will also log lines like:

Dec 13 12:15:29 x250 NetworkManager[388]: <debug> [1481627729.0469] dhcp4 (wlp3s0): creating composite 
dhclient config /var/lib/NetworkManager/dhclient-wlp3s0.conf
Dec 13 12:15:29 x250 NetworkManager[388]: <debug> [1481627729.0469] dhcp4 (wlp3s0): looking for existing 
config /etc/NetworkManager/dhclient-7111201a-568f-4568-a0ed-cd1d4df11e8f.conf
Dec 13 12:15:29 x250 NetworkManager[388]: <debug> [1481627729.0470] dhcp4 (wlp3s0): looking for existing 
config /etc/NetworkManager/dhclient-wlp3s0.conf
Dec 13 12:15:29 x250 NetworkManager[388]: <debug> [1481627729.0470] dhcp4 (wlp3s0): looking for existing 
config /etc/NetworkManager/dhclient.conf
Dec 13 12:15:29 x250 NetworkManager[388]: <debug> [1481627729.0470] dhcp4 (wlp3s0): looking for existing 
config /etc/dhcp/dhclient-wlp3s0.conf
Dec 13 12:15:29 x250 NetworkManager[388]: <debug> [1481627729.0471] dhcp4 (wlp3s0): looking for existing 
config /etc/dhclient-wlp3s0.conf
Dec 13 12:15:29 x250 NetworkManager[388]: <debug> [1481627729.0471] dhcp4 (wlp3s0): looking for existing 
config /etc/dhcp/dhclient.conf
Dec 13 12:15:29 x250 NetworkManager[388]: <debug> [1481627729.0471] dhcp4 (wlp3s0): looking for existing 
config /etc/dhclient.conf
Dec 13 12:15:29 x250 NetworkManager[388]: <debug> [1481627729.0471] dhcp4 (wlp3s0): no existing dhclient 
configuration to merge


<<<<<


But can you not just configure ipv6.dhcp-send-hostname and ipv6.dhcp-
hostname:

  nmcli connection modify $NAME ipv6.dhcp-send-hostname yes \
    ipv6.dhcp-hostname wibble.example.com


Thomas

Attachment: signature.asc
Description: This is a digitally signed message part



[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]