noseka1

How to disable AAAA lookups?

Problem description

The corporate DNS server that is outside of our control doesn't handle AAAA queries properly. When sent a AAAA query, the DNS server doesn't respond. A properly working DNS server returns NOERROR, ANSWER: 0, if there is no AAAA record for a given name. Misconfigured DNS server doesn't send any response.

In an IPv6-enabled environment, the client tries to resolve both A and AAAA addresses. If the DNS server doesn't send any reply, the client repeats the query and eventually times out. Only after the AAAA query times out, the client will use the A address. Waiting for the timeouts renders utilities like curl, kubectl, oc, ... and others unusable.

Identifying the AAAA lookup problem

ndbroadbent

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