rec: allow_no_rd - document cache contents on root on startup pertaining to dig ...

diff --git a/pdns/recursordist/settings/table.py b/pdns/recursordist/settings/table.py
index e16200c7d11e708318c2c1826179766cadfa7704..4772bbdc56d76714ca40b5550f5a5733c3eb4f57 100644 (file)
--- a/pdns/recursordist/settings/table.py
+++ b/pdns/recursordist/settings/table.py
@@ -203,6 +203,10 @@ Like :ref:`setting-allow-notify-from`, except reading a sequence of `Subnet`_ fr
         'doc' : '''
 Allow ``no recursion desired (RD=0) queries`` to query cache contents.
 If not set (the default), these queries are answered with rcode ``Refused``.
+
+Note that there is a short while after restarting that the cache has no authoritative data on the root,
+so it will answer with an NODATA (NOERROR and no answer records) in that period for RD=0 queries
+affecting for example older versions of dig when using its +trace option.
  ''',
     'versionadded': '5.0.0'
     },