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I want to use IPv6 locally but I don't have an external IPv6 connection. External lookups are slow.
Author: ISC Support Reference Number: AA-00206 Views: 5038 Created: 2011-03-24 15:22 Last Updated: 2016-12-22 00:39 0 Rating/ Voters

On some networks, IPv6 is used internally, but is not supported by the link to the rest of the internet. This degrades resolver performance due to named attempting to send IPv6 queries that can never be answered.

To prevent IPv6 queries outside the network, while still allowing them inside, use a pair of server clauses:

server fd81:ec6c:bd62::/48 { bogus no; };  // site ULA prefix
server ::/0 { bogus yes; };

This allows IPv6 queries to be sent to addresses in the fd81:ec6c:bd62::/48 network prefix, but not to any other IPv6 addresses.

IPv6 can also be disabled entirely by using the named -4 command line option.

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