Problems with our migration from MS to BIND this weekend

Ryan McCain Ryan.McCain at
Mon Sep 24 16:17:36 UTC 2007

So, even though BIND complains about them I shouldn't experience any odd behavior on the server if underscores are being used?

>>> On Mon, Sep 24, 2007 at 11:02 AM, in message
<F17FA75D-0303-4178-94AD-3C608D964DC2 at>, Chris Buxton
<cbuxton at> wrote: 
> BIND 9.2.x and earlier did not perform the same name syntax checks  
> that later versions of BIND 8 did. Thus, many people assumed this was  
> by design, and that BIND 9 no longer minded seeing underscores in  
> records.
> BIND 9.3 and later does a name syntax check and will (by default)  
> refuse a zone containing underscores. (Since the underscore is now a  
> standard character for a few record types, you might think ISC would  
> have added them to the allowed list by now.)
> You can configure this behavior by adding the following into your  
> zone statement (for each zone that you want to allow underscores):
> 	check-names warn;
> You could also put in this:
> 	check-names ignore;
> The former will log a complaint when underscores (or other invalid  
> characters) are discovered in a zone. The latter will not. The  
> default behavior is:
> 	check-names fail;
> You can also set this globally in the options statement by adding  
> another argument, either master or slave (and there's a third  
> category, but I forget the name). The defaults are:
> 	check-names master fail;
> 	check-names slave warn;
> Since I have not taken the time to double-check what I've just  
> written (it's all written from memory), you should verify all of the  
> above in the BIND 9 ARM.
> Chris Buxton
> Men & Mice
> On Sep 24, 2007, at 8:47 AM, Ryan McCain wrote:
>> While doing the change I came across conflicting information on  
>> whether underscores are permitted.  We do use Active Directory and  
>> many of it's SRV records use underscores.  Is this a problem?
>> Does anything special need to be done in BIND to get it to work w/  
>> Active Directory?
>> Thx..

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