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How do I restrict only remote users from looking up the server version?
Author: ISC Support Reference Number: AA-00308 Views: 2530 Created: 2011-05-16 14:22 Last Updated: 2017-01-25 01:20 0 Rating/ Voters

The following view statement will intercept lookups as the internal view that holds the version information will be matched last.  Note doing this will not prevent attacks and may impede people trying to diagnose problems with your server. Also, it is often possible to "fingerprint" nameservers to determine their version from the way they respond to specific queries.

view "chaos" chaos {
     match-clients { <those to be refused>; };
     allow-query { none; };
     zone "." {
             type hint;
             file "/dev/null";  // or any empty file

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