I have the following error message in my /var/log/spamd
spf: lookup failed: available_nameservers: No DNS servers available!
Having Googled the error message I've found a number of responses which
involve patching Perl or Spamassassin or other cures.
Before I start changing things I was wondering if there was a Centos 7
specific resolution. Where possible, on production machines I prefer to stay
with RPM's rather than amending software directly.
Also, many of these responses are over 10 years old, so I'm a little sceptical
about their success today.
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