[atlas] RIPE Atlas anchor resolver update

Dear colleagues,

All the RIPE Atlas anchors run a caching DNS resolver. This resolver is
used to look up names when a measurement requests name resolution using
a probe's resolver.

We have been running an older version of BIND for this service.

In the coming days, we will be upgrading the version of BIND to the
latest stable version (9.14). This version has dropped many work-arounds
for various forms of brokenness in other DNS implementations. The effect
of this is that a small number of domains hosted on broken DNS
implementations cannot be looked up by this newer version of BIND.

If you are running a measurement that uses an anchor's local resolver,
and you find that some domain names are failing to resolve, it may be
caused by this upgrade.

Regards,
Anand Buddhdev
RIPE NCC