Re: dhcp6 and fqdn support (for dns)

[Gene Czarcinski <gene czarc net>]

On 09/17/2012 02:36 PM, Gene Czarcinski wrote:
> On 09/17/2012 02:24 PM, Gene Czarcinski wrote:
> > On 09/17/2012 12:05 PM, Jiri Popelka wrote:
> > > On 09/16/2012 09:55 PM, Gene Czarcinski wrote:
> > > > BTW, from the info in the dhcp-options man-page, I believe that 
> > > > NetworkManager should be doing "send fqdn.fqdn" instead of "send 
> > > > host-name" for IPv4.  This should be with a plain name ... not a 
> > > > qualified name.  See the man-page.
> > > The story behind this is
> > > https://bugzilla.redhat.com/show_bug.cgi?id=694758#c20 (NetworkManager)
> > > https://bugzilla.redhat.com/show_bug.cgi?id=697877 (initscripts)
> > >
> > > > OK, bug or feature?
> > >
> > > Well, me and the original reporter of those bugs had suggested to 
> > > "send fqdn.fqdn" when $(hostname) was FQDN and "send host-name" 
> > > otherwise, but Bill Nottingham (initscripts) decided to always "send 
> > > host-name". So I thought it would be better for NM to stay 
> > > consistent with initscripts.
> > > Read those BZs and if you think the behavior is wrong you could try 
> > > to re-open them.
> > I have not gone back to look into the history of what should or 
> > should not be sent.  I only looked at what is said in the current 
> > (Fedora 17,  dhcp-common-4.2.4-9.P1.fc17) dhcp-options man page.
> > ------------
> > option fqdn.fqdn text;
> >
> >  Specifies  the  domain name that the client wishes to use. This can 
> > be a fully-qualified domain name, or a single label. If there is no 
> > trailing  ´.´  character  in the name, it is not fully-qualified, and 
> > the server will generally update that name in some  locally-defined 
> > domain.
> > -----------
> >
> > It also says that "options fqdn.hostname" and "option 
> > fqdn.domainname" should never be set.
> >
> > When I got things to work, there was a lot of options in the lease 
> > file in addition to fqdn.  I am not sure exactly what needs to be 
> > specified except that for IPv6 if I specify "-F <homtname>" on the 
> > dhclient command line, things work. For IPv7 "-H <homename>" seems to 
> > work.
> >
> > Regardless, as things now work I do not get dynamic dns update for 
> > IPv6 (works fine for IPv4).  This has been with dnsmasq as the dns 
> > and dhcp server.  I am not setting up testing on qemu/kvm/libvirt 
> > with a guest running named and dhcpd instead of dnsmasq.  My 
> > expectation is that it will not do dynamic dns either.
> >
> > My reason for pushing this is that while using radvd to help with 
> > IPv6 address assignment works for a client-only situation, it soon 
> > falls apart when I have a bunch of systems referring to each other. 
> > For IPv4 using addresses only is painful, for IPv6 it is impractical.
> >
> > I believe that such situations will needs either a IPv6 dhcpd with 
> > DDNS to named or a dnsmasq.  I do not know, there might be other 
> > packages out there but these seem to be common.
> https://bugzilla.gnome.org/show_bug.cgi?id=684242
I have duplicated the situation but instead of using dnsmasq for dns and 
dhcp services.

I installed and configured named, dhcpd, and dhcpd6 on the server an 
started them.

On the client, disable networking and stop the NettworkManager.service.  
Again, the small change in the ifup-eth network script to use "-F" 
instead of "-H" and on dhclient commandline for "-6" and "ifup eth0" 
works its magic.   "host xxxx" now provides both IPv6 and IPv4 addresses.

Gene