ftp.perl.org strangeness

[Dave Hart]

I've run across this issue with a few websites in the last 18 months.
It might help to ask if they're using a "load balancer" on
ddns5.develooper.com (the nameserver for ddns.develooper.com which is
the zone containing ftp.cpan.ddns.develooper.com which is CNAMEd from
ftp.perl.org).  One DNS-based load balancing product exhibited this
broken behavior, though I don't know which product it was.  When queried
for type A or any type, the correct responses are returned, but when
querying for AAAA, NXDOMAIN is returned, which is evil because it
communicates false information that there are no records of any type at
that name.  Since IPv6-enabled clients query AAAA before A or any, they
tend to trip up 100% of the time.  I've not yet heard of a
general-purpose DNS server getting this wrong, I assume any such
offenders were fixed earlier in the 8 years of AAAA.  DNS-based load
balancers are on average greener.

I ran across this first with a major computer reseller website and
complained to their admins.  It took many months for them to get the fix
from their load-balancing vendor and convince themselves it was safe,
but they did eventually correct the fault.

ask <at> develooper.com is listed as the contact in the SOA for
ddns.develooper.com, hopefully including them on this email will get the
ball rolling.

Dave Hart
davehart at davehart.com