BIND9 reject characters in host names

jlinkels · 02-10-2006, 09:24 AM

I noticed that bind9 version 9.3.1 (from the Debian testing distribution) does not accept certain characters like "_" (underscore)

I have another machine running DNS with bind9 9.2.4 which does accept this.

Unfortunately I have set up another machine for which I needed some files from the testing distribution, and I cannot install bind9 9.2.4. For different reasons this new machine *has* to become DNS server.

I don't get it. In some bind version, the option check-names was introduced to reject for characters which were not allowed. It is stated explicitely that in bind9 this option is removed and that all characters *are* accepted. To make it worse, bind9 will not load a zone file with a single error at all.

I have a local network with some tens of machines, with names like star_pc.mydomain.com. The underscore is there for historical reasons. (When our DNS was still on the windows platform, long time ago) Changing all the host names both in the zone file and on the hosts *is* doable, but these host names are also used in numerous settings in applications (like in mail clients etc), and that is NOT doable to change it there.

Does someone know whether this is a bug or a feature in bind9? Is it intentional? Is there a newer version which does not do check-names?

jlinkels

jlinkels · 02-10-2006, 10:00 AM

Almost at the instant of the previous post I solved the problem by including the check-names directive in the (named.conf or named.conf.local for Debian) file.

It looks now like this:

Code:

zone "mydomain.com" {
     type master;
     file "/etc/bind/mydomain.db";
     check-names ignore;
//   check-names warning; <== This also allowed.
     };

I was confused, because this site states that check-names is not implemented in bind9. Later I discovered that ics.org states that it is back (or new) in bind9 version 9.3.

Anyway, it took only 6 hours or so to work this out

I hope it was not useless to post this experience here... although many of you are smarter than I am.