Different signed serial numbers

[Nick Tait]

On 24/09/2025 21:36, Alessandro Vesely wrote:
> On Wed 24/Sep/2025 08:25:40 +0200 Nick Tait wrote:
>> On 24/09/2025 05:42, Alessandro Vesely wrote:
>>> The script I ran just issues a few queries using Python's 
>>> dns.resolver.  I don't see how it could check for consistency (or 
>>> determine that some resolvers use different views).
>> The tool you're using might be looking at NS records and then 
>> querying the authoritative servers directly, possibly in addition to 
>> the asking the configured resolver?
> The script is https://github.com/hannob/alwaysdns.  It is charmingly 
> simple in its downloading and comparing all SOA records.  I assume 
> signed serials have definitely disqualified this synchronization 
> checking technique.  Are there any alternatives?
>
>> (What do the internal zone file NS records point to? And when you 
>> "copy the (edited) internal zone file to the public one, replacing 
>> things like NATted addresses", are you also updating those?)
> This is an old bash script I've been tinkering with for years. 
> Internal and public zones live in two parallel directories.  For each 
> internal zone file it generates the public copy on a temporary file 
> using sed.  If that temporary is different from the current one, all 
> .jbk, .signed, .signed.jnl of that zone are marked for deletion.  If 
> there are any files so marked at the end, named is stopped, the files 
> are removed, and named is restarted. The script doesn't check the 
> serial numbers.

Looking at the script it does indeed appear to be using the resolver to 
query the domain for NS records, and then querying each name server for 
its SOA record, and comparing the serial numbers. This is basically the 
same as what you would get by running "dig +nssearch /domain/".

It sounds like the NS records in your internal zone file include both 
internal and external authoritative servers? If so you can remove the 
external ones and the problem should go away? You'll just need to make 
sure that when you "copy the (edited) internal zone file to the public 
one, replacing things like NATted addresses", you also replace the 
internal NS records with the external ones?

Nick.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.isc.org/pipermail/bind-users/attachments/20250925/aead8ec8/attachment.htm>