[master] change DATASRC_QUERY_NO_ZONE from INFO to DEBUG

using debug level of 40 for now.

This is for ticket #1102.

Also clarify the log description.

No changelog entry.

Discussed some on jabber.

src/lib/datasrc/data_source.cc

@@ -384,7 +384,8 @@ doQueryTask(QueryTask& task, ZoneInfo& zoneinfo, RRsetList& target) {
     const Name* const zonename = zoneinfo.getEnclosingZone();
     if (ds == NULL) {
         task.flags |= DataSrc::NO_SUCH_ZONE;
-        logger.info(DATASRC_QUERY_NO_ZONE).arg(task.qname).arg(task.qclass);
+        LOG_DEBUG(logger, DBG_TRACE_BASIC, DATASRC_QUERY_NO_ZONE).
+            arg(task.qname).arg(task.qclass);
         return (DataSrc::SUCCESS);
     }
 

src/lib/datasrc/datasrc_messages.mes

@@ -569,8 +569,10 @@ An attempt to add a NSEC3 record into the message failed, because the zone does
 not have any DS record. This indicates problem with the provided data.
 
 % DATASRC_QUERY_NO_ZONE no zone containing '%1' in class '%2'
-Lookup of domain failed because the data have no zone that contain the
-domain. Maybe someone sent a query to the wrong server for some reason.
+Debug information. Lookup of domain failed because the datasource
+has no zone that contains the domain. Maybe someone sent a query
+to the wrong server for some reason. This may also happen when
+looking in the datasource for addresses for NS records.
 
 % DATASRC_QUERY_PROCESS processing query '%1/%2' in the '%3' class
 Debug information. A sure query is being processed now.