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

Re: taming resolv.conf

Digby Tarvin wrote:
> On Wed, Apr 16, 2008 at 05:16:16PM -0600, Bob Proulx wrote:
> > Digby Tarvin wrote:
> > > My new /etc/resolv.conf is coming up as:
> > > nameserver
> >
> > This is correct if you have bind9 installed.  Since this is
> > automatically detected then I assume that you do have bind9 installed
> > in order to see this result.  If you remove bind9 then you would see
> > the DHCP nameserver addresses there.
> >
> > In which case there is one manual step to installing resolvconf.  You
> > would need to change:
> >
> >   include "/etc/bind/named.conf.options";
> >
> > To this:
> >
> >   include "/var/run/bind/named.options";
> >
> > The resolvconf package scripts know about bind9 and if it is installed
> > then they assume that you want to use it and automatically set up
> > /var/run/bind/named.options with the nameservers offered by DHCP.
> >
> > Bob
> Aha! Yes, that was it. Thanks!
> Just removing bind9 was enough to produce the expected behaviour. 

Yes, but "your expected" != "my expected".  :-)

> Not sure I follow the bit about the manual step required. Which file
> is it that is being edited? can't find anything in etc/resolvconf..

See the /usr/share/doc/resolvconf/README.gz file for the details:

  3.5 bind9
    * Change the /etc/bind/named.conf file so that it includes
      /var/run/bind/named.options instead of /etc/bind/named.conf.options.

> Or is that a step which would allow use of the DHCP values with bind9
> still isntalled?

Yes.  That is exactly what it allows.  Then you get all of the
benefits of a caching nameserver.

> I suppose the latter would be useful to be able to do, so that all my
> servers could be configured to run off a single nameserver, but be
> able to take over as the nameserver with a simple change of config
> if desired. (I am setting one up for a friend that wants to give
> debian a try, but is not experienced in Linux admin, so fairly simple
> but flexible network adaptability would be a big advantage)

Not quite.  That isn't really what this particular step is doing.
Certainly bind9 can be configured to forward to a specific set of
nameservers but that would be a separate and unrelated step.

What this step is doing is configuring bind9 to use the resolvconf
updated list of dhcp offered nameservers.  The bind9 named will then
act as a caching nameserver forwarding to them.

When the network interface is brought up or down then resolvconf runs
hook scripts that will update whatever needs to be updated.  The list
of dhcp nameservers is one of the pieces of data that gets updated.


Attachment: signature.asc
Description: Digital signature

Reply to: