[CentOS] DNS bind - use of /etc/named directory

Fri Dec 7 15:39:04 UTC 2018
John Horne <john.horne at plymouth.ac.uk>

On Tue, 2018-12-04 at 00:51 +0000, John Horne wrote:
> For many years we have modified the '/etc/named.conf' file to include local
> settings. The disadvantage with this is of course that when bind is updated,
> it creates an '/etc/named.conf.rpmnew' file. We then have to determine what
> is new, and apply the relevant changes to our modified named.conf file.
> There is, however, an '/etc/named' directory which I assumed was for local
> configuration settings. The main '/etc/named.conf' file makes no mention of
> this directory, so (I suspect) any config files in '/etc/named' would, by
> default, just be ignored.
> As far as I can tell we could put our local configuration settings into a
> file in '/etc/named', but we would then, once again, have to modify
> '/etc/named.conf' to tell it to include config files in '/etc/named'. We
> would then be back at square one in that any bind update would create an
> 'rpmnew' file.
> I admit I haven't actually tested this, but has anyone used the '/etc/named'
> directory and not had to modify the main '/etc/named.conf' file?
I finally got round to giving this a test. Unfortunately unless you are adding
new configuration sections, or zones, then it does not work. I wanted to add
some extra 'options' settings and placed them into an
'/etc/named/local_named.conf' file. (The '/etc/named.conf' was modified to
include this file.)

Upon starting bind/named though it complained with
"/etc/named/local_named.conf:2: 'options' redefined near 'options'"
because I had defined the 'options' section in my new config file, as well as
it being present in the supplied default '/etc/named.conf'.

So, in order to add extra options settings, I see no way other than modifying
the supplied '/etc/named.conf' file.

Note: it may well be possible to 'include' a file within the '/etc/named.conf'
options section, provided that file only contained 'options' settings. In our
case we also want to modify the logging section slightly, so we would need
another include in the 'logging' section. Overall, we would end up modifying
the '/etc/named.conf' file with include files just as much as if we just added
the new options directly to it. Trying to use '/etc/named' in our case is just
not worth it.


John Horne | Senior Operations Analyst | Technology and Information Services
University of Plymouth | Drake Circus | Plymouth | Devon | PL4 8AA | UK

This email and any files with it are confidential and intended solely for the use of the recipient to whom it is addressed. If you are not the intended recipient then copying, distribution or other use of the information contained is strictly prohibited and you should not rely on it. If you have received this email in error please let the sender know immediately and delete it from your system(s). Internet emails are not necessarily secure. While we take every care, University of Plymouth accepts no responsibility for viruses and it is your responsibility to scan emails and their attachments. University of Plymouth does not accept responsibility for any changes made after it was sent. Nothing in this email or its attachments constitutes an order for goods or services unless accompanied by an official order form.